RE: OS SR 60?
If this is the OS .60FSR you have a jewel. It was used in pattern competition and is a very reliable engine. Yes, parts can still be found on the net or Ebay. Just have to look. Should you really need parts, I think ASP is a clone. The backplate fit mine, I had to use 3 gaskets for spacing as the con rod hit the base of the plate. Have flown many times since, no problems.