I have OLD super tigre G40,,,BLUE head engine...can someone please tell where I can get a new piston and sleeve and the ORIGINAL muffler,,,,I want to use this in 424 pylon...I also would like to find a como40 (supertigre's cousin)

We're sorry, but your engine's old enough that parts are no longer available for it. The only way you'd be able to locate parts might be through RCU's Marketplace from a modeler or dealer who has those parts, or from one of the online auction services. You might want to try checking in the model magazines for those hobby retailers who sell parts and engines to the collectors' market. They usually place small ads in various places in the magazines, or advertise in the classified sections.