Mz moskito sx build help

[Bba]

I have a 2002 mz moskito sx. Engine number CPI 50c*014042*. I got it from a guy who changed the cylinder and piston in it because the original piston broke a ring and scratched up the cylinder wall. When he started it up it ran then quit. When he took the head off the piston was broke. I've tried googling the engine number and can't find what's compatible with mine. I tried using the numbers and letters on the cylinder and still can't find anything. Please help. The original cylinder number are 3xg00 49cm square. On the cylinder he replaced it with is 3xy00 49cm square. What piston do i need to get for 3xy00 cylinder or is that one not compatible with my motor? If it's not which ones are? I would like to be able to get the scooter up to at least 60mph in the future.