Saw this at Red Rock Canyon S.P. in California, on a recent trip.
    http://www.sportsmobile.com/2_sr-penthouse.html
Stopped to talk to the owner and his wife, and had a look inside. Mentioned the thin
mattress in the Westy, and she pointed to the upper bunk mattress and it looked to be
about 8" thick!
Everything looked really nice inside and then they told me it was made by
$portsmobile$$$. At that point, decided not to ask about the price, because, well, you
know, I could afford one, but it wouldn't fit in my garage!
Jerry in AZ
P.S. On their home page, they have a picture of a vintage VW bus with a wild
conversion.