Barry,
the cost to convert from long axles to short was about $300 as I ended up buying everything from one of the transmission companies. I suspect the cost of the parts from a fellow VW person could be a lot less. Ususally there are people wanting to go from short to long, not the long to short direction. By the way, converting the axles is a bunch of work and not necessarily easy. If you decide to do it we should talk first, might save you a few mistakes that I made.
The cost of the front and rear disk brake kits from SoCal was just over $1000. Installation was no big deal other than I had to make an adaptor for the emergency brake cables (yours may be different). Installation time was no more than a few hours. The biggest hassle was changing out the master cylinder (part of the kit) and getting the pushrod to master cyl adjusted properly....
The cost to change out the rims and tires was as follow:
rims $50 each = $200
powdercoat rims silver, $62.50 each = $250
tires, Yokohomas, mount and spin balance (weights on inside only) $320
I did all the work myself, mostly just standard tools needed, other than the clip rings on the axles in the Super Diff. You could save perhaps $300 by using Type 3 drums on the back of the car, I went with 4 wheel disks myself, I was never happy with the stopping with drums on the back.
Jim