I would recommend going to a truck repair shop, they will have the facilities to handle this size of vehicle. Our local Ford dealership can do the medium duty truck servicing but couldn't do alignments.
We have a local Cummins facility that is part of the Coachcare network, I take our RV there for servicing of both the engine\drivetrain and generator. They can do other repairs except body work, and I'm sure could do an alignment.
Coach Care RV Service Centers | Funroads RV Travel
I can't help with costs, sorry. We had our coach aligned within a few months and it was covered under the Forest River warranty. Our dealership doesn't do alignments, but took it to the truck service center next door that they work with and took care of everything, I never saw the bill.
Tom