Are you referring to the crank gear
(sometimes calles a toothed pulley)
or the alternator/water pump pulley?
If you need the crank gear, you can
get one, new, from Python Parts
part #5010-63374 for $18.04 (Cdn).
If your referring to the alternator pulley,
contact burn_your_money on this forum
he may have one.
He seems to have a lot of things (and,
occasionally, stuff) for Mk2 Diesels.