Can you purchase? Probably not. Most likely the camper is wired in a non-standard way compared to a trailer.
That was what happened with my Palomino. It has a standard 7-pin plug in the front, but it's wired different from a trailer.
You'll need to figure out which pin does what, and if there is a 12V pin. Draw a picture of the connector on a piece of paper with plenty of room around it to make notes. With a battery in the camper, use a piece of wire to briefly jump any two pins together. Just a quick tap. If you get a spark, you found 12V and ground. To figure out which one, switch to a different pin on one end of the jumper. If nothing happens, you now know which of the first two pins are 12V and ground. If a light comes on, again, you know which is which. Take notes. Now start poking between the 12V and the other pins on the connector and see which lights come on as you do that. Take notes.
Now you can get a 7-pin, a 6-pin and enough cable to reach, and make up your own custom connector.
In your case it will be easy to know which end plugs into the truck and which plugs into the camper. In my case I put it in backwards once and nothing worked right. I had to raise the camper back up to get at the plug in my bed to swap ends on the cord. Then I wrapped tape on the truck end. T is for tape, and for truck.
Putting 10-ply tires on half ton trucks since aught-four.