if that part number is correct, then a lot of places have it. Here is a
picture
http://www.bus-ok.de/bilder/produkte/gross/T3-Dichtung-fuer-Druckring-fuer-Drehfensterachse-Lagerwinkel-und-Vorreiber-orig-VW-Verglnr-281837745_b2.jpg
or here:
http://www.jimellisvwparts.com/products/Volkswagen-VW/Vanagon-syncroShort-engine-for-automatic-transmission----------------------also-use/Gasket/5287163/281837745.html
seems Rabbits, Jetta etc from that time period had the same.

On Thu, Apr 28, 2016 at 5:20 PM, Richard A Jones <Jones@colorado.edu> wrote:

> I looked on etka.cc and got 281837745 (seal) for the part.  BusDepot lists
> it as a special order for $1.79.  I don't know if they really can get it.
> The ETKA diagram shows the same part for the hinge and the window lock.
>
> Richard
>