Here is the build I d potentially do:
Asus Impact Motherboard M-ITX (1- PCI-E slot with built in sound). This board has not released yet, but it should be out shortly and looks spot on.

Video Card:
http://www.superbiiz.com/detail.php?name=AT-7950BST#

Sapphire 7950....this specific model is the card I would suggest. Video card manufacturers start on what is called a "reference design". That means they use the components, boards, and GPU required by AMD. Later on they change to their own components and board while using AMD's GPU. Sometimes they use higher end components, but often they are cutting corners to make higher profits. This board is a reference design, and if you ever decide to watercool it can accept a reference block with ease (not that I think you will watercool). This cooler is one of the best and will cool the GPU, VRMs, and VRAM excellently all while being very quiet. A true reference cooler will cool quite well, but it will sound like a damn air plane taking off inside of your computer. Superbiiz is a reputable internet company and if Newegg or Amazon does not carry this exact model I would order form them. If it comes down to it Bubu, I will gladly ship all the things from my house to you that cannot be ordered directly. I extended the same invitation to Incinerate. I know people have trust issues and all, but you can take that up with me personally. I offer to do so in order to save you guys cash. A friend of mine lives in Paraguay and I understand the high prices in a lot of South American countries and companies unwilling to mail internationally.
Processor:
http://microcenter.com/single_product_results.aspx?sku=583302

Dirt cheap at Microcenter, but they are in-only. I have one about 2 hours from me and I pass it all the time visiting friends and family in neighboring cities. Best Buy will often pricematch as well and ship, the international thing might be the only issue, but I once again offer to help. This is $40 cheaper than Newegg, and they also shave off $50 if you purchase a motherboard through them. If they carry the Asus Impact Motherboard then that will be a total savings of $90.
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Case:
A few options based on your tastes-

http://www.newegg.com/Product/Product.aspx?Item=N82E16811163208
Great case with good flow and super compact. It might be a little tougher to put together, but it is a good performer and is nice and compact for travel or tight living quarters.
Corsair 350D

http://www.newegg.com/Product/Product.aspx?Item=N82E16811139020
Good for air and watercooling. Has a nice clean look and the non-windowed version is on sale for 69.99 after rebate. Don't forget this is a M-ATX case so it can fit M-ITX and M-ATX boards, this might be handy if your next build is M-ATX.
Lian Li PC-Q25B

http://www.newegg.com/Product/Product.aspx?Item=N82E16811112339
Lian Li cases are all aluminum and great build quality. This one has a great minimalist look and decent ventilation. The highest price, but cases last for years and several builds. Only weighing in at 6.8lbs. With board and card you can stay under 10lbs probably.
Bitfenix Prodigy

http://www.newegg.com/Product/Product.aspx?Item=N82E16811345016
A very spacious and appealing case with a ton of modding options. They also come in some nifty colors as well. The case looks good, has nice rubber handles, easy to install a window in, and adequate spacing for watercooling as well.
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If the budget demands it I d just go with an 8GB kit for 2400MHZ ram. If some extra cash is in the budget I would snag 16GB of 2133MHZ ram or go for a larger SSD or something. Or a nifty watercooler.

http://www.newegg.com/Product/Product.aspx?Item=N82E16820231638
The above is Gskill Trident X ram which is in my wife's computer. It has great speeds and good CAS latency. Ivy Bridge and Haswell can handle higher MHZ RAM but past 2400 the returns are not noticeable in gaming. 2133 MHZ is just fine as well and still above the majority. This kit comes with a nifty cooler that has a blue LED if that matters. It is not loud and does help move some air across the nearby components.
G skill Sniper 2133 MHZ

http://www.newegg.com/Product/Product.aspx?Item=N82E16820231518
Good timings, good speed, and color scheme isn't bad. It saves $15 over the above kit and is a good fall back if the budget needs tightening.
Last is the extra budget set:

http://www.newegg.com/Product/Product.aspx?Item=N82E16820231617
16GB of 2133mhz Gskill Trident with good timings as well. The highest price, but you get twice the ram and surely will not need more.
As far as whether to get 16GB vs. 8GB it is relevant to what you're doing. If it is just gaming, then 8GB should be fine. I cannot say, how demanding the up and coming games will be, but currently 8GB is just fine and I wouldn't recommend any less. If I was going to risk something in the budget it would probably be this so that I could have more of something else. RAM is often cheap and easily obtainable and retains value quite well, which means you can sell it off and pay a little more for a 16GB kit down the road if necessary. That $60-90 could go towards a SSD hard drive that is much larger or possibly a watercooler.
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CPU Coolers
Two options really exist at this point and it depends on budget as well. Water or air. If the budget is really tight you can buy a cheap an pretty efficient air cooler. If you have a few bucks left over I d highly recommend either the Cooler Master Eisberg 120L/240L or Swiftech H220. The awesome thing about these is that they work really well, quiet, and they are expandable without voiding the warranty. These are the only all in one water coolers like this, most have to weak of pumps to support any additional crap. This are super easy to install and if you get into it later you can watercool the GPU, motherboard, or RAM( completely unnecessary). A really good air cooler will run you $90, with the Swiftech being $139, it gives you a lot of leeway for $50 and cools better with less noise. I have installed two of these personally (one on my wife's) and I enjoy the unit a lot.

http://www.newegg.com/Product/Product.aspx?Item=N82E16835103183

http://www.newegg.com/Product/Product.aspx?Item=N82E16835103184

http://www.newegg.com/Product/Product.aspx?Item=N82E16835108183
Air Coolers:
http://www.newegg.com/Product/Product.aspx?Item=N82E16835709011
http://www.newegg.com/Product/Product.aspx?Item=N82E16835608018&IsVirtualParent=1
Both of those have good reviews and are fairly quiet. I am not sure if it will work with Socket 1150, which is Haswell, so we need to wait and see.
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Hard Drive:
I'll come back to this. If your old hard drive can be re-used I would do it to save cash, and if budget allows grab a 128-256gb SSD.