I just purchased a NOS US Military Haldex Pure Air Plus off eBay "24 VOLT MILITARY TRUCK ABS AIR DRYER PURE AIR PLUS M939 A1 A2 M923A2 M35A3 M925" from vendor "fastcashmoneyman". I asked him if he had any more as I thought someone might be able to use one and for the price it is cheaper than rebuilt and has all new parts included. He stated that he did have one more left that did not have a box so I take it that might be a bit cheaper but that would be up to you to negotiate with Will on that one through eBay. The installation instructions I got were for the (N4250A/DA33110) which is the 24V but just above that is the number for the 12V (N4250/DA33100) so it is the same animal that a lot of us use. The photos are of the one I just received so this is what you would be getting.
You would only have to buy a 12V heater (late model assembly after '97). The installation guide that was with it was Rev. 2/02 which I would take that a being 2002 vintage paperwork so the unit would be pretty much the same. Also, it comes with a new mount which could be attacked to a bench or trailer hitch for when you need to rebuild your next one. It would be certainly easier using a strap wrench on it as I don't thing you would move the coach twisting the canister off, just an idea. I paid $279 and change plus shipping which in that no core charge and no tax to pay out.
Also, he does a pretty big surplus business and has many more NOS Air Dryers to sell from vendor such as Haldex and Bendix so whatever you may need just ask as he may have one. Take note though it will be under a military part designation. Good luck!
John
Moved here since this isn't a member-owned classified.
I think I have the same one here. Wrong one for our coach without redoing the hoses. So I had the dealer rebuild the original one,
Anyone who wants this please contact me.
Came from the same guy if memory serves me