Bit over, but this should last some time:
PCPartPicker part list:
https://uk.pcpartpicker.com/list/2hrM8Y
Price breakdown by merchant: https://uk.pcpartpicker.com/list/2hrM8Y/by_merchant/
CPU: AMD - Ryzen 5 1600 3.2GHz 6-Core Processor (£150.97 @ Amazon UK)
Motherboard: MSI - A320M PRO-VD PLUS Micro ATX AM4 Motherboard (£43.98 @ Ebuyer)
Memory: G.Skill - Ripjaws 4 series 8GB (2 x 4GB) DDR4-2400 Memory (£59.30 @ Amazon UK)
Storage: Western Digital - Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive (£35.99 @ Aria PC)
Video Card: Palit - GeForce GTX 1050 Ti 4GB StormX Video Card (£149.99 @ Overclockers.co.uk)
Case: Cooler Master - MasterBox Lite 5 ATX Mid Tower Case (£37.99 @ Amazon UK)
Power Supply: SeaSonic - FOCUS Plus Gold 550W 80+ Gold Certified Fully-Modular ATX Power Supply (£69.95 @ Overclockers.co.uk)
Total: £548.17
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2018-03-12 10:54 GMT+0000
Down the road, simply swap out the 8GB kit for a 16 GB, and the GPU too. PSU is very reliable here.
Later on, also consider a swap for the mobo.