Yeah, you're right something like this might be more appropriate.
PCPartPicker part list / Price breakdown by merchant
| Type | Item | Price |
|---|---|---|
| CPU | Intel Core i5-4590 3.3GHz Quad-Core Processor | £155.94 @ Aria PC |
| Motherboard | MSI H81M-E34 Micro ATX LGA1150 Motherboard | £38.17 @ Scan.co.uk |
| Memory | Kingston Fury Black Series 8GB (2 x 4GB) DDR3-1600 Memory | £50.99 @ Amazon UK |
| Storage | Crucial MX100 128GB 2.5" Solid State Drive | £52.11 @ Amazon UK |
| Storage | Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive | £34.45 @ Aria PC |
| Video Card | PowerColor Radeon R9 290 4GB PCS+ Video Card | £199.99 @ Amazon UK |
| Case | Fractal Design Core 1300 MicroATX Mini Tower Case | £32.98 @ Amazon UK |
| Power Supply | EVGA 500W 80+ Certified ATX Power Supply | £33.59 @ Aria PC |
| Prices include shipping, taxes, rebates, and discounts | ||
| Total | £598.22 | |
| Generated by PCPartPicker 2015-02-16 14:58 GMT+0000 |
I didn't really have the time to make a perfect build, was just pointing out that OP might be better off building his own or trying to get a bit more money off. To be honest if you're patient and wait for sales you could possibly get a 290x in there for about the same price.