I have actually looked at several places including that one and they all say the exact same thing. Either you buy the whole piston with rings or nothing. The rings, even under the parts for the K532 say for K582 only in parentheses. I even have the original parts list that says the same thing. I have also seen them on ebay and the description always has a warning that "these will not fit a 20hp engine they are for 12hp" and they usually say for engines with serial# after XXXXXXXX. I guess Ill probably have to reuse the old ones if I cant figure this thing out. Maybe Ill try to post a pic of the diagram with parts so you guys can see what Im talking about.