I'd give Colin a call. He is the only one able to order OEM Henschen axles now, and he is the only one we use for Airstream axles.
I've tried getting Dexter axles from Redneck, but after having to return 3 sets of axles because either the brackets were mounted wrong, starting angle was wrong, shock brackets are not available and had to be welded on after delivery, ez-lube hubs instead of standard, I swore I'd never get Dexter axles again unless they made some radical changes (or I had a gun pointed at my head). So far, neither has happened. If someone inists on selling you Dexter axles, make sure you are aware of their return policy, in case you have problems like I have had multiple times.
Meddle not in the affairs of dragons, for you are crunchy, and taste good with ketchup.