Take the camper weight and add 800 lbs and that is the weight you will be hauling with the truck. If you stay with a 1000 lb or less popup camper the 1/2 ton will be fine. Borderline is a 1800 lb camper like the Lance 825. The 825 will be OK but the weak link is going to be the tires provided by the factory but these can be changed.
With a new truck I would negotiate on having the dealer put in tow mirrors and better tires to get the load capacity you expect to need. This is also a good time of year to get a good deal on a 2013 2500 truck that is sitting on a dealer's lot in your state.