Found one here:
Maquette de la fin des années 60, très difficile à dénicher.
www.ebay.com
Moebius Interstellar Ranger
I have seen paper models of it offered online; I just might try doing one using the templates in plastic just to see if it can be done.
UPDATE: found one on Scribd (sign up for a free account and upload a document to get the download free):
Interstellar Ranger | PDF