Mike,

That thin little plastic sticker around the slider handle hole is there to
protect the paint from the escutcheon that move a bit when operating the
handle.  The escutcheon for the '84 is NLA, but do a search on eBay for
"delrin vanagon" and someone is making a nice replacement part.  I
replaced my escutcheon with the derin one and it's a nice fit. The seal
you mention that is missing is a foam ring, that was missing on mine as
well and I got a replacement one from the Bus Depot a few years back.  I'm
not quite sure what that seal does, it might simply be a dust seal.  When
you replace the screw that holds the handle, make sure to put a drop of
blue loctite on it's threads.

Pascal
'84Westy