Many in the Montana line come stock with self adjusting brakes. As mentioned come from Dexter as a complete assembly. If you're a member of an Owner club and if they have annual Rallies you might be able to get a good deal. Dexter was offering a good deal at the recent Montana Rally as an upgrade for unit that didn't have them.
2011 Chevy Silverado 3500HD LT Ext Cab 4x4 Duramax/Allison, 2016 Redwood 39MB, Disc Brakes, Mor/ryde IS, GY 17.5" H tires, 5.5K Onan, Dual ACs, auto level, auto sat dish, stacked washer/dryer, residential fridge, King sleep number. Michelle & Ann