Since you're using Amazon, check out Flubit. You won't get Prime delivery, but you will get around 10% off.
I assume you know you're build will be £531 at least.
Also, that PSU will struggle. It's not very efficient, and the load is very close to its maximum. Get the Antec True Power Classic. 550W, Gold, and a fantastic model.
With this in mind, I've made some suggestions. Take what you want from them. Just my opinion.
PCPartPicker part list / Price breakdown by merchant
| Type | Item | Price |
|---|---|---|
| CPU | Intel Core i3-4150 3.5GHz Dual-Core Processor | £89.64 @ Amazon UK |
| Motherboard | ASRock H81M-HDS Micro ATX LGA1150 Motherboard | £43.66 @ Amazon UK |
| Memory | Kingston 8GB (1 x 8GB) DDR3-1333 Memory | £53.00 @ Amazon UK |
| Storage | Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive | £40.99 @ Amazon UK |
| 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 | Antec TruePower Classic 550W 80+ Gold Certified ATX Power Supply | £50.80 @ Dabs |
| Operating System | Microsoft Windows 8.1 (OEM) (64-bit) | £72.99 @ Amazon UK |
| Total | ||
| Prices include shipping, taxes, and discounts when available | £584.05 | |
| Generated by PCPartPicker 2015-02-05 17:39 GMT+0000 |