There's one out of Oklahoma I've seen a couple of times in Fort Worth. The camper part looked like a period box rather than a modern RV. But of course with windows and 2 AC units on top.

"It's just a phase. He'll grow out of it." Mama, 1964

1956 Chevy 1/2-ton 3100
1953 Chevy 6100 "The Yard dog"
1954 GMC Suburban Now with a new proud owner.