You have the first version ENYA .049 . It is a reed valve engine. The 049 II is a front rotary valve engine. You need to run fuel with 20% Castor Oil for lubrication. The crank runs in the Aluminum crankcase without any bushing. The piston is Iron running in the steel sleeve. Enya produced the .049 and .06 as reed valve engines, later the .049 II, the .06 II, the .08, and the .10 as front rotary engines. As far as we can tell, these engines were not sold in North America. Not many people have seen them. I have a pair of .049 II engines and a pair of .06 II engines. Mike Keville has been flying his entries in the Pheonix multi engine profile scale competition with the 06 II engines.
Have fun with your engine.
Pat