A version of the passenger ship designed by von Braun and Bonestell for the Collier Magazine's early '50s symposium on travel to Mars is now available on the Motherlode on the "fictional spacecraft" page.
(After Anim8or crashed while writing its output file, I decided it was time to "declare victory" and make it available.)
The model is in binary CMOD format, so you'll need Celestia v1.3.2 or later to view it.