CR480 / '84 CR500 / '85 CR500 Common Parts??

[madmcnish]

Hi folks,
I've been offered an '84 as a restoration project.
The rolling chassis looks complete (but rough) and most of the engine parts are there. The LHS crankcase is missing and I've been told that the gearbox may also be shot.
I'm aware that the '84 was a 1-year-only model and is the only year of the air-cooled 500 so am concerned that parts may be hard to find if I decide to go ahead with the resto.
Are any parts shared with the CR480 or the '85 / '86 CR500's?
Thanks for any advice.
Ross