Greetings loco_greengo!
Welcome to the Forums and the world of Vintage Airstream ownership!
The VIN tag on most Vintage Airstreams is on either a cast plaque or an aluminum plaque immediately to the right of the door either at belt-line level or rub-rail level depending upon era. Later model Vintage Airstreams have VIN plates behind the LP tanks below the front window. I have attached pdf files containing information on interpreting Airstream VINS.
The Henschen Dura-Torque axles appear to be original to the coach, and based upon the length of time that it has remained parked they are likely in need of replacement prior to contemplating many road miles. To get the coach home, you will want to repack the wheel bearings which will give you the opportunity to inspect the brakes as well. The brakes are likely Kelsey Hayes or Dexter, either of which have ready parts sources. You may find that you only want to make repairs necessary to get you home, and hopefully you will find the only problems to be rusted springs (available in replacement kits) or one or two other small components . . . it is always best to compare the cost of needed parts with the cost of fully loaded backing plates as it doesn't take too many individual parts to approach the cost of a fully loaded backing plate.
You can assess the condition of your coach's axles using the information in this
link. You can also learn about the configuring of a hitch for your Vintage Airstream at this
link.
Good luck with your Vintage Airstream!
Kevin