I know the wiseco rings and pistons crossed over just fine, but the oem rings changed (I think they went to a taper type design for more compression) - the early ones may work in the later pistons tho', but I seem to remember something different regarding the pin configuration (maybe set at a different height?). Then again, trusting my memory for over 20 years ago is iffy...LOL...
Regarding wiseco, I'm in the process of rebuilding an 87 and it has a wiseco piston in it, so I read the numbers on the piston top. Some guy is selling an old (but unused) wiseco piston from back in the day on ebay, it had the same part numbers and I could also read the ring part numbers on the ring package that came with it. Wiseco uses the same ring part number today so I just ordered a set for a bike that hasn't been worked on for 15 years or so. Pretty cool.
01 KDX220 03 yz125 forks & triples, FMF rev, silencer, 607 reeds, rb head mod, rb striker
87 KDX200 04 yz250f forks & triples, H model rear disk brake, FMF pipe, boyesen reeds
91 Suzuki RMX250 plated
'08 WR250R (the dual sport)