Where can I get a needle valve and gasket and bolt set for this Engine?

We'd have no idea.  The engine has been out of production since the 1970's or so.  You'll have to go online to an auction site or check in the magazines for dealers who sell parts to the engine collectors' market.  They advertise in small ads or in the classified section at the back of the magazine.

Thanks anyway ... I think I will check for a work around using some one elses parts ... once again ... thank you
Leo