Regardless of where you get your secondhand drives do yourself a favor and make sure they package them correctly (antistatic bag, 1-2inches of bubblewrap and a cardboard box) by messaging for that. That’s my biggest complain when I brought used drives. Think Serverpartdeals and goharddrive are the main eBay sellers with great reps but I sadly haven’t done business with them so can’t verify
I rather buy used ssds off eBay from a known brand.