Get the r9 radeon 290 $195 =gtx 970 3d mark score :15210
Gtx 960 $209 3d mark score: 10500
just so you know even if you upgrade your graphics to high end, but your current cpu will drag its performance down.
but however you should able to run 30fp-40 fps in high setting with r9 290
because i m pretty much running the same specs as you... if you upgraded to r9 290 however...
thats y i m upgrading my cpu to 4790k XD should be getting 60 fps afterward, especially survival of the fittest i m getting 10 fps!!
the cpu bottleneck is real!!!Anyway,r9 290 is used but it's the best gpu i can pull out of with an extremely cheap price,50% more powerful than gtx 960 with a even cheaper price!! Gpu is super durable and don't break unless it's overheating!i bought 2nd hand pc hardware all my life never run into any problems
http://www.ebay.com/itm/AMD-XFX-Radeon-R9-290-GPU-Reference-/291543185573?hash=item43e153f8a5
http://www.futuremark.com/hardware/gpu