A "parade" Dodge would be something different, but what about one of these?
All the room in the back can be filled with jerry cans to keep the truck running with the extra fuel consumption it would take to drive it all the way through Europe
Serious; I think finding a suitable WC54 wouldn't be too much of a problem as they are offered quite regularly. Carryall might be a little harder and more expensive. The websites Hanno posted are a good start.
Alex