I've done several BW-65 Transmissions.  Never did a Vanagon/VW though.
Here's what I found.  The local "rebuilder-gouger" is set up to rebuild an
on the bench transmission in about an hour for which he will charge you
~500USD in parts and "labor"  NB this doesn't include the R&R which is rated
around 2-3hrs depending upon whose "flat-rate" tables you believe.  A good
mechanic can do the r&r in under two hours.  So with the r&r and rebuild you
should see ~4hrs.  Lesser competence implies longer times for the job.

A check of a local wholesale only parts place had the rebuild kits,
complete, for ~100USD.

My advice for the adventurous is to contact your local experienced parts
purveyor and buy an experienced (you don't know where it's been)
transmission, have your local friendly mechanic shop buy you the kit at
wholesale plus tip or from a list vendor.  Rebuild the recently acquired one
using the kit.  Go slowly and carefully and be meticulous regarding
cleanliness and re-assembly.  Labelling an egg carton for storing small
parts has proven useful in the past.  Ziplock and label all the bits as you
remove them.  Sequence the bags.  The next rebuild will be much less of a
mystery.

Make copious notes and ... post em to the list with pictures on the
alternate list.