Engine rebuild parts 98 400

Hey guys and gals. I’ve got a 98 Foreman 400 I’m looking for some parts to rebuild engine. Where is the cheapest place to get them at? I have low compression and would like to at least get a set of rings and new piston but may also replace bottom end parts as well. She has right at 10,000 miles and just gave up the ghost;) turns over great and am really thinking it might be a valve but am just gonna rebuild it. Thanks in advance y’all.