I can't build a PC specifically for Tarkov, but this is what I'd consider for 2K, minus OS, keyboard, mouse and monitor:
AMD Ryzen 5 7600 Six Core 5.10GHz (Socket AM5) Processor - Retail -
£239.99
Asus TUF Gaming B650-Plus (Socket AM5) DDR5 ATX Motherboard -
£219.95
Corsair Vengeance EXPO 32GB (2X16GB) DDR5 PC5-48000C36 6000MHz Dual Channel Kit - Black (CMK32GX5M2D6000Z36) -
£179.99
Zotac GeForce RTX 4070Ti Trinity 12GB GDDR6X PCI-Express Graphics Card -
£799.99
WD Black SN770 2TB SSD M.2 2280 NVME PCI-E Gen4 Solid State Drive (WDS200T3X0E) -
£149.99
Lian Li LANCOOL 215 Mid-Tower aRGB Tempered Glass Black -
£89.99
MSI MPG A850G PCIE5 UK PSU 850W 80 Plus Gold Modular Power Supply -
£179.99
Alpenfohn Glacier Water 280 High Speed ARGB CPU Water Cooler - 280mm -
£129.94
Grand Total: £2,001.82 (includes delivery charge)
To make some room in the budget for the peripherals, you could dump the AIO and get an air cooler (case height restriction and motherboard clearance permitting) like the Thermalright Peerless Assassin (
review), slower memory (e.g. 5600 C36) and a micro-ATX case and board, like the B650M-DS3H.
Would need to check AIO thickness for top mount in the 215 (OCUK's specs suggest it would fit, but on their website, I don't think it would).