Welcome to iRV2
As ; slowmachine ; mentioned , search " Dodge Sportsman" or " B series" van, in that vintage, and you should get what your after .
The Sportsman name plate on those years of vans , was an indication of trim level ( better seats,dash trim ,headliner) as opposed to the bare bones Tradesman vans .
1973 Tradesman B 200 , was my second brand new vehicle , and I did my own conversion to an RV . Oh to be young and foolish again.
EDIT: While I was typing , this I see , slowmachine has posted a good question .
Do you have a Class C , or; as in the photo he posted , a Mini Winni class A on a Dodge chassis?