Where to buy an RV mattress like the bunk mattresses?

I've been sleeping on a higher end air mattress in my RV for 15 weeks or so as I travel around. It is the most comfortable mattress I have ever had. Brand is Aero Bed. Has a built in air pump and only takes a minute or 2 to fill. Probably doesn't weigh more than 10-15 pounds.
However, if you're going into the or driving through mountains, you better remember to let a lot of air out. As you gain altitude, the air inside expands. Don't want any loud surprises while driving.