'82 Air cooled Westy a/c

................If it's never been serviced in recent years, you'll probably
need a rebuilt/exchange compressor from NAPA or Carquest. With a core
exchange I'd guess that you're looking at a couple of hundred for it. Then
you'll need to charge the system with the old style freon that's supposed to
destroy the ozone layer in the stratosphere but they've discovered recently
that the ozone layer is doing just fine after all. Then, you'll need to
determine whether the dryer is OK and that there aren't any small leaks in
the system to drive you crazy because they're really hard to track down
sometimes. Before you proceed, you'll be needing the Bentley manual for
vanagons that's about $90 the last time that I looked. Aside from something
like a new compressor, most of the system can be  replaced without VWoA
parts that are way way overpriced. Is it reasonable to try to get it
working? Depends on what your needs are and how much time and expense you're
willing to expend.