Never oil a camera heavily. Camera oil is very thin special watch oil. We sell it. Parts for cameras are not hard to find. Get them off junk cameras.
Many parts are interchangeable between different makes of camera.
An equal mixture of household ammonia and medicinal hydrogen peroxide applied with a swab removes fungus from the glass of lenses. Mix just before using. Windex is as good a lens cleaner as any. A Making ground glass. Simply get a piece of good clear glass of the right thickness as your old ground glass.