On our 2 previous 5th wheels, I replaced the Coleman Mach analog thermostats with the Coleman Mach digital, model 66363441. Very easy swap, wire for wire swap and mounting was exact as the anolog. A quick look online just now shows me ridiculous prices for them though and out of stock issues. I got mine on Amazon both times for about $75-$80....now I am seeing well over $200!
RVupgrade.com shows them at $138, but out of stock.
Might be best to look at a residential thermostat from Lowe's or Home Depot. I don't have experience with those but many folks on here have used them successfully.