Yes, it’s from 1938 but we can presume that it was used in southern California in 1939. Be sure to click on the image link for full details.
“Dr. Hubert Eaton was a very savvy businessman, whose name is forever linked to the Forest Lawn Memorial Park cemeteries in California, where many celebrities and public figures have found their final resting place. Eaton was also probably painfully aware that, in order to have success, one must project a successful image, much like today’s real estate agents will do when they make sure they buy (or rent) an expensive supercar.
“This belief and the desire to experience the best in terms of road travel led to the creation of what is today an iconic motorhome, the 1938 Vagabond. The Vagabond is a very unique rig, made of a custom REO bus and an equally custom Curtiss Aerocar trailer, one of the first luxury fifth-wheelers in history.”
“…The towing vehicle was a ‘38 REO cab-forward hauler, custom-built by Standard Carriage Works of Los Angeles.”
Excerpts from the image link above.
Image: Photo courtesy Orange County Archives via 
1939 Southern California 