> 	What year or model Vanagon came with the 15" alloy wheels????

An easy one!  NONE.

My 15" alloys are probably Audi 5000 Turbo wheels -- the only 15" alloys
with VW markings that I know of.  There is a steel 15" wheel also for
Audi that fits (it even has the same part number as the alloys).  The
Audi wheels need some machining to fit.

malcolm