Cool trailer. I bought a '76 Argosy 6 Meter Minuet [20 footer], back in March, '06. Argosy was Airstream's '70s experiment with a lightweight trailer. They are all-white in stock form. The nose and tail sections are made from stamped galvanized sheet steel, the "fuselage" section is aluminum skin just like the Airstream. The "Minuet" series are only 7'6" wide instead of the full 8' for even a Bambi A/S.
www.airforums.com is a website that covers all Airstreams and Argosys, even the vintage units. Lots of helpful oldtimers there. I'm still a lurker there. There's alot of lore to absorb before sounding off.
My Argosy is considered a 20 Footer. It has one axle. It tows pretty well behind my '71 Jimmy 4x4 (350/SM465/NP205/3.73 Posi.) However since mine's still a project, I haven't taken it anywhere yet.