From the little I have heard, I believe that the first year for the actual 'Airstream' name to be on a motorhome was '79. The Argosy and Airstreams were both produced that year. I'm not sure whether there was any difference at all other than the Argosy being painted and the Airstream left in aluminum. I'm not sure whether there is any difference in the end caps as there are in the Argosy trailers. The Airstream motorhomes were more differentiated later.
AIR 2053 Current: 2006 Born Free 32 RQ Kodiak Chassis, & 1995 Coachmen B-van
Former Airstreams: 1953 Flying Cloud, 1957 Overlander, 1961 Bambi, 1970 Safari Special, 1978 Argosy Minuet, 1985 325 Moho, 1994 Limited 34' Two-door, 1994 B190 "B-Van"