RE: OS Max .61 SF (Ringed)
Most parts specific to the O.S. Max SF/RF series of engines are no longer available through regular retail channels, through us, or from O.S. in Japan. The engines went out of production in 1995 or so. You'll have to ask through the RCU Marketplace, an auction service, or one of the hobby retailers who 'scrounge' parts for engine collectors. Those retailers usually advertise in small ads in the model magazines.