With that camper they will be at the top of their towing capacity if they have the full towing package. If they have the 3.73 gears the tow rating is dropped to 8500lbs and that means they'd be over. I have a 2015 316 BIK (Just a tad bigger than the 313) and I upgraded to a 3/4 ton truck because of those issues. We love our Sprinter and they were about 8-10k less than a comparable Fiver with a similar floor plan.
2010 Dodge Ram 2500 Laramie Megacab 6.7 Deleted, Tuned, Leveled and LOOKING GOOD!
2015 Sprinter Wide Body 316BIK