If you decide to rebuild the G50B, most of the parts you need can be found on ebay, including the CDI ignition. Right now, all I see are flywheels for the liquid-cooled models, but if you keep watch I'm sure some for the air-cooled engines will show up. The ignition is the same for both, but the flywheels for the liquid-cooled engines don't have a provision for a ring gear and you won't be able to use your electric start. Right now there are both NOS and aftermarket pistons listed for the engine. I've used both with good results. Good Luck, NCT.
Stuck in the seventies- not in the swamp.
(6) Attex, a Hustler, a Super Swamp Fox, (2) Tricarts, (3) Tri-sports, a Sno-co trike, 3 Dunecycles, and a Starcraft! ...so far