I guess it is a little to late to let you know that most how carry a camper also have a 1 ton truck and many of those are dually trucks because a 11' long camper is going to be at least 3,000 pounds and with slide outs, it can be 4,200 pounds! That is a lot more than your F-250 can take. At least you have the lighter weight 6.2L engine and have the increased GVWR of the newer trucks.
I had a 460" 7.5L engine in my 1975 Ford F-350 with a 9,600 GVWR and curb weight around 6,500 pounds. I could safely carry another 3,100 pounds according to the paperwork that came with the camper package. I had a cheap camper on it when I bought it in 1987. In 92, I bought a 1972 Coachman camper that had a forward bath taking up the front 3' and dinette behind that on the passenger side, kitchen on the drivers side. Dinette was raised about 8" to give it a place to put the black tank. Back in the 70's grey tanks where rare, and I did not have one.
My factory engine HP rating was probably around 225 HP. Yours flows much more air, can wind up to 4,200 RPM and run there all day long, while mine did not have nearly as much power. You have plenty of power, and the ability to tow any size travel trailer. Fifth wheels and campers are another subject, as you don't really have the weight capacity to carry a large camper or tow a heavy fifth wheel.
Good luck finding something!
Fred.