As indicated on another thread - I picked up a refurbed corporate PC, HP Elite 8300 i5-3470 3.2ghz 4gb, stuck in a 120gb Crucial SSD all for under £100
As of a few moments ago I have ROCK running and both my OSX formatted USB drives visible
7k+ albums and it’s as fast or better than the iMac I’m freeing the Core from - another £10 will double the RAM so I might try that when feeling rich 