I've run a 9' pop-up on my 2006 Dodge diesel 3/4 ton, just added air springs. And use the Happijac tie-downs mainly because of the weaker beds in that year than in say.... the '70's.
Now putting on a restored 2400-2800 lb 8.5', max custom for systems, but still very small in size (and really in weight). I'm wild guessing the weight at this time.
I won't tell you to buy a 3500, but if I were to go bigger than what I have had or intend I'd either buy a 3500 or have a spring shop set me up right for at least suspension. I think my brakes, frame and axles are rated higher than the 2500 status, but springs just might get you.
Good luck, you've just started asking the right questions. I wouldn't hesitate to look close at several brands, but maybe some of the smaller Northstar campers would work for you. Wolfcreek another good lighter outfit (meaning no slides and smaller wall thickness than their heavier cousins, Arctic Fox). Lance is a good choice, but can be heavy, I think. Any slide will knock your truck out of the running without more mods.