I've seen them for sale on evilbay, Craigslist, and Hemmings a few times. Better have good, brakes, springs and shocks with that baby on the roof. If it's fiberglass it probably weighs a ton. I had a fiberglass cap on my '76 El Camino and it took two men and a boy to lift that thing on and off.
That just looks like an accident waiting to happen. It doesn't look that securely fastened either. One rack-type connection on the roof; wonder what the back end connected with - the bumper? It blocks the rear window and tailgate access too. An Airstream is 1000 times cooler!
It looks like an over-sized outhouse is trying to have its way with the wagon....and the wagon doesn't look happy about it.
I got outbid on the one on Ebay last year by a few bucks !!! they are called a Totemotel...and they are pretty freekin cool...not cute...but cool !! I still want one