Check the online parts microfische to see if they share the same crankcase and crank. You want to make sure the connecting rods are the same length so that port timing matches up. You may also need the 700 pipe, stator and CDI, and any other engine management electronics. Engines may share the same bottom end, but it will be more than just cylinder bore that makes them different. Look around for good used cylinders, or contact a replater and buy without exchange.