Martin,

FWIW here is my 2 cents:

You're going to spend a lot of time and money fitting a TDI into
your Van so why would you want to risk installing a junkyard
trans?  The newest transaxle you can get is already 15 years
old and who knows how many miles are on it?  I'd strongly
recommend a rebuilt, unless you enjoy yanking all the TDI stuff
out just to swap gearboxes when the 'junker' trans doesn't work.
Try Karl Bloss's guide for VW shops at:

www.enter.net/~bloss/vw/vwshops

Even if they can't help you they should know someone else in
your area.  If that doesn't work out then send me a p/mail and
I can build one for you.

Todd Hill
VolksWerks Transaxles  //  VW dealer mechanic
Olympia, WA