A little late to the party but with relevant information.
I've been involved in the Canadian Mercedes Benz circles for a LONG time. I've also been a long time offroader. My first vehicle was a 1989 Jeep YJ. Suffice it to say that I, too, had been keeping my eyes open for a decommissioned/surplus Canadian Forces G-Wagen.
The information that I was given was that the Canadian Forces were contractually obligated to return any, and all, G-Wagens to Daimler when they are done with them. Whether they are in working order, or not. Whether they are in one piece, or not.
It's possible that a handful _may_ have slipped through the cracks, but not very likely.