If you want more power for your 200 look into the 225 kit from eric gorr I believe it use's a 220 piston and you get porting and head mods. The $430 price tag was worth it to me.
A buddy of mine has a 220 jug on his 200. It's a 220 now. I don't know where he got it or what he paid for it. You can call FRP. He's got lots of used KDX parts. Of course, I don't think it makes it "faster", it just gives it more bottom end. Porting the cylinder might be the best bang for buck.