a friend of mine is in San Marcos Texas and sent me these pictures. Apparently this is one of one Prevost MHs built in 1951. It was owned by a gentleman from Montana.
With all those bus windows, looks like it was built as a passenger coach and converted. Nicely restored. I've seen some really rough coach conversions from the 50's and 60's on the road, it is nice to see one that looks good.
Oldest cherry coach I've seen was a really early Newell, from when they were building all aluminum and using gas Ford big-block industrial engines for motive power.