Short bed or long bed?
Most short bed capable length campers have wet baths aka phone booth. But many have good water/tank capacities.
If you have a long box, you have more options for a dry bath.
If you’re hung up on the weight then yeah you’ll need a bigger truck. If you’re not, and your truck is in good shape, it is effectively the same as a 3500 srw of the same year and many years newer.
Again, provided the truck is in good mechanical and structural condition, I wouldn’t have issue going up to around 4klbs on that truck with the right mods.