Doing a search brings up all kinds of elaborate tents which fit on the back of a truck but they have pretty involved setup and are expensive. Actually a friend of mine has been trying to sell me one which his wife got with her Jeep but it is much more than than what I want.

The closest I have been able to find is not available in US and not designed for a truck with a cap:

https://www.reimo.com/en/93792-rear_tent_vertic_for_caddy_floor_space_w135xl135/

I think that my options are to contact a canvas shop for something custom, sew my own which is far beyond my sewing ability or go the blue tarp bungee cord PVC pipe pole route. For the few times I will use it the blue tarp is probably the best.

This all started when I sold my camper because my wife did not really care to go along and I figured that if I am alone I can just sleep in the back of the truck. I have used the camper as a base camp on state forest land or campgrounds and do day hikes for a couple of days of laid back relaxing.