Yes, that is what I aid: 72" belts are available from most major manufacturers in 2", 2.5" and 3" from most belt suppliers. You would have to change out the wheels to run a 2X72 with wider belts.
I got the wheels from a machine shop that was closing. They had contact wheels up to 12" wide.
You should be able to get them from places like industrial suppliers (McMaster-Carr?).
I'm sure Sunray has wider contact wheels.
Also, any good machine shop will make the aluminum wheels for you.
I bet Greg at Reeder will make a set. You could probably order his basic chassis with the wider wheels. Give him a call.