Ah right ok fair enough.
You could still look for something like a Ryzen 3 3200G and then just need to source a AM4 board, something like a B450/B550 which should be cheap 2nd hand. Would allow option to upgrade CPU later on if needing more power later on.
Not sure these days what other companies can be named here, but CEX could be an option and would give some warranty. Otherwise could try the usual online places.
Looks like the mini-itx sized boards are selling for more of a premium 2nd hand online.