Where is the VIN on 1963 VW BUS?

a couple of places...or at least it should be.

Open your engine decklid, and look on the metal body area near the #1 spark plug (between the engine and the battery.) It should be imbossed into the body of the car. If that area is cut out, it was likely junked at one point in its life.

Look behind the passenger seat.

Look on the passenger side of the fresh air vent on the roof.

A 1963 bus VIN has 7 numbers.