I last got mine back in 98 I believe. Here is a old message I posted not long after.
"I was able to go to a locl napa and get new valves, springs. The part numbers are 211-1038 Exhaust valve; 211-1037 Intake valve; 218-7411 exhaust valve seat; 218-8463 Intake valve seat; 212-1015 Valve springs. The product line for all of them are NEP. If you need gaskets here is the address and phone number where I got mine- Olson"s Gaskets 3059 Opdal Rd. E., Port Orchard, Wa. 98366 Ph. 360-871-1207. They will ship anywhere. Otto gas engine works has gaskets and some other parts in stock also. (www.dol.net/~dave~reed/otto.html). Good luck, and if you need help with anything else let me know!