Volkswagen Bus, Vanagon, Eurovan Distributors, Caps and Parts
Vacuum advance distributors were made, for a long time, by Bosch in Mexico. These have not been available for years ! The only brand new distributor that we offer is the "mechanical or centrifugal advance" distributor. It works well if you are not fanatical about absolutely optimum performance. It does require careful timing procedures. Here is a great set of instructions (you may have to copy and paste this url to your browser): http://www.vw-resource.com/009_dizzy.html
There are high quality distributor rebuilding specialists out there.You can consider the rebuilding of an original VW distributor. Here is one with an excellent reputation: Ignition Engineering in Anaheim, California. You can "google" distributor rebuilding and locate others.
You can also consider converting to electronic ignition.