If you're strictly gaming and not doing any video editing/streaming/etc, you can go with an i5 build.
Here's a build to consider:
The i5 is a better gaming cpu than the 8350 because its stronger in single threaded applications. It'll still handle well in games to come. Its still an overclockable cpu if you are into that or maybe consider it later on.
Cooler: water cooling is a bit too expensive, and the hyper 212 evo is enough for a nice overclock anyways.
RAM, cas 9 1600mhz should be the minimum for gaming.
GPU, the r9 280x is stronger than the gtx 760.
case, Unless you really want the other case, i changed it to lower the price a little bit. It wasn't much of a difference if you want the other case.
PSU: XFX 550w is better than the CX 600w. The XFX is a seasonic unit and has better parts compared to the CX600w. Under stress the xfx can last longer than the cx600w.
PCPartPicker part list:
http://uk.pcpartpicker.com/p/ppXmFT
Price breakdown by merchant: http://uk.pcpartpicker.com/p/ppXmFT/by_merchant/
CPU: Intel Core i5-4690K 3.5GHz Quad-Core Processor (£157.99 @ Aria PC)
CPU Cooler: Cooler Master Hyper 212 EVO 82.9 CFM Sleeve Bearing CPU Cooler (£24.25 @ Scan.co.uk)
Motherboard: MSI Z97-Gaming 3 ATX LGA1150 Motherboard (£87.94 @ Scan.co.uk)
Memory: Team Vulcan 8GB (2 x 4GB) DDR3-1600 Memory (£54.21 @ Amazon UK)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive (£38.70 @ Aria PC)
Video Card: XFX Radeon R9 280X 3GB Double Dissipation Video Card (£189.99 @ Ebuyer)
Case: Corsair 200R ATX Mid Tower Case (£44.99 @ Amazon UK)
Power Supply: XFX 550W 80+ Bronze Certified ATX Power Supply (£44.11 @ CCL Computers)
Optical Drive: Lite-On iHDS118-04 DVD/CD Drive (£9.58 @ Scan.co.uk)
Operating System: Microsoft Windows 8 (OEM) (64-bit) (£71.99 @ Ebuyer)
Wireless Network Adapter: TP-Link TL-WN727N 802.11b/g/n USB 2.0 Wi-Fi Adapter (£5.10 @ Aria PC)
Total: £728.85