Wanted - Passenger seat for 1982 SilveWing GL500 interstate Thanx

Hello I'm looking for parts for my new GL500 interstate. Eg: passenger seat, oil and air filters, plugs etc. I have encountered differences between the user manual and what people and wesites say. Can anyon ehlp me with a source for part numbers? Or just the parts numbers for the above? Thanx

Hey guys, I just recently purchased a passenger seat for my black 1981 GL500 to replace the cargo trunk, not realizing there would be a gaping hole leaving my toolkit exposed. Looking to purchase a cowl, doesn't have to be in great condition, preferably black, though ill be painting my bike...