We are 3300 on the pin with a gcwr of 22800 loaded (we are legal to 25,000). Pulling a 2014 351 RSTS with a 2013 Ram 3500, 6.7 Cummins, SRW. I had a dually before this truck but I prefer this truck for all round driving.
Specifically to the question, get a one ton. For the extra $3k you will have towing piece of mind. Can you do it with a 3/4 ton? Sure....probably.
2013 Ram Longhorn 3500 Crew Cab 6.7 Turbo Diesel, Aisin Transmission.
2014 Jayco Eagle Premier 351 RSTS, Mor/Ryde Suspension and Pin Box, 17.5" wheel upgrade, 18k Pull Rite hitch.