The only thing I would suggest is change your GPU to an equally powerful AMD Radeon HD 7000 Series card. AMD plays nicely with its own cards, probably better than it does with Nvidia's cards. Also, I would not get the bare minimum Power Supply requirements. I would go for at least 50-100 more watts than the graphics card requires. Other than that, that is a pretty solid build. May I suggest the Sapphire Radeon HD 7850 OC Edition? It is normally $144.99, but there is a mail-in rebate that takes it down to $129.99, and that should fit quite nicely into your build. Plus, it can play all of your games quite nicely.
As a rule, the graphics card is more important to the gamer than the cpu.
I might reallocate your combined budget on a 2 for 1 basis. reallocate to $65 for the cpu and $130 for the graphics card. That might be a G2020 ivy bridge dual core and perhaps a GTX650ti boost or a 7790.
8gb of ram is good, but buy a 2 x 4gb kit so you can use dual channel.
A stock cooler will do the job; the one you listed is really no better.
Coolermaster is not considered as good quality as corsair for power supplies.
You will probably want more than 400w for any of the cards mentioned. 430 or 500w would be better.
You might find this NZXT source 210 case will save you a bit: http://www.newegg.com/Product/Product.aspx?Item=N82E168...