If WoW is your main game id get a 1060 and a 1440p monitor actually, your CPU is fine its a shame you dont have a p67/z68 motherboard to overclock tho.
1060's are hard to find right now, but here is a 1440p monitor on sale for 249.00:
PCPartPicker part list /
Price breakdown by merchant
Monitor: Acer G257HU smidpx 25.0" 60Hz Monitor ($250.98 @ Newegg)
Total: $250.98
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2016-07-29 12:24 EDT-0400
Neweggs site seems to be down atm, but thats a good price for a 1440p screen. As for GPU just keep an eye out on nowinstock.net, the only one i would stay away from is the zotac mini, it has a really poor cooler on it. The msi armor is a good model for 249.00.