I interpreted the OP as saying they are looking for a basic camper that may be marketed for a 1500 but they are planning on putting it on a larger truck. In 2017 we traveled over 10,000 miles with our Ram 2500 2WD and an Adventurer 80RB (2480 lbs loaded) and the stock truck with only a Hellwig sway bar performed flawlessly.
We now have a slightly heavier (and better equipped) Travel Lite 840 SBRX (2600 lbs loaded) and I just added a mid grade set of airbags today.
As others have said, half tons typically have pretty small payload capacities and secondly, manufacturer published weights are often times a base weight that is meaningless. There are a few companies that publish the actual weight on a separate sticker inside the cabin as well as the base weight on the outside.
Our Ram 2500HD with the 6.4L Hemi has a payload capacity of 3575 lbs so there's some opportunities out there. The wheels and tires are well beyond the 10K lb GVWR.