I would go one step up the stream and hold the manufacturers accountable for this. I did a lot of research for over a year before buying the truck camper we have, a Northern Lite 8.11.
You can go to any of the manufacturers web sites and they will all tell you they have a lot of campers that will "fit" a 3/4 ton truck or higher. My F250 I had to carry my NL was well overweight based on the payload, axle and GVWR numbers. Now, could the truck handle it? sure it could handle it but the big question is, "will it SAFELY carry it?"
I determined that for me, being that I am in the transportation industry, it was not safe. It cost me some money to upgrade my one year old F250 to a 2017 F350 but at the end of the day, I feel safe now hauling my camper and gear and know that if I should be involved in an accident, they will never be able to say I was carrying something I knew was not within the specs and guidelines of my truck.
I am not a weight nazi but I am amazed, after going through my experience, at how many clearly overweight campers are on the road.
So, back to my original point, the manufacturers need to be more forthcoming in this area and the reputable dealers will follow suit.