You could also look for a FX8320 or FX8350 on the cheap now that ryzen has come out.
Added the cpu cooler to the 2nd one, but if you have a suitable one now that's not needed.
On the other hand if you don't the 212 evo is a good choice with the first set too
Going with intel and using your existing memory:
PCPartPicker part list:
https://pcpartpicker.com/list/cp96dC
Price breakdown by merchant: https://pcpartpicker.com/list/cp96dC/by_merchant/
CPU: Intel Core i5-4690K 3.5GHz Quad-Core Processor ($235.99 @ Jet)
Motherboard: Asus Z97-A/USB 3.1 ATX LGA1150 Motherboard ($119.56 @ Amazon)
Total: $355.55
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-03-23 16:27 EDT-0400
Updating to the latest generation intel.
PCPartPicker part list:
https://pcpartpicker.com/list/jpCfCy
Price breakdown by merchant: https://pcpartpicker.com/list/jpCfCy/by_merchant/
CPU: Intel Core i5-7600K 3.8GHz Quad-Core Processor ($233.49 @ OutletPC)
CPU Cooler: Cooler Master Hyper 212 EVO 82.9 CFM Sleeve Bearing CPU Cooler ($24.88 @ OutletPC)
Motherboard: Asus PRIME Z270-AR ATX LGA1151 Motherboard ($163.95 @ B&H)
Memory: GeIL EVO X 16GB (2 x 8GB) DDR4-3000 Memory ($109.45 @ Jet)
Total: $531.77
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-03-23 16:29 EDT-0400