You can fit G-Wagen wheels without any problem to go for 16". One of the toughest vans out there, you can find them everywhere in Afrika, carryting 20+ people and tons of luggage on "roads" worse than anything you will find in the Americas... if only they didn't rust so badly!
Parts are easy to find, and anyway, not much to go wrong as tey are quite simple vehicles, and easy to work on, as long as you don't need to get the engine out. Had a 1980 207D for years, took me all over Europe, good old days!