Enterprise truck rental (NOT regular Enterprise locations!) will let you tow with a 2500 or 3500 rental. They're the only national chain other than U-haul that explicitly allows it in their contact, and unlike U-haul they rent crew cabs so you can take the family. If you have the ability to setup a business account Herc and United rentals are also options.
As far as insurance coverage, no mine does not have nearly a high enough daily limit on rental coverage to get a truck, though I could probably just do it and cover the difference.
