Neat Wanderer! I have yet to see one of those in person.
I don't know anything about the condition of your '68 or how far you have to tow it home, but I doubt it needs a new axle. The old DuraTorques tend to fail gracefully, the rubber just takes a set and doesn't give you as much "spring travel" as it should. Put new tires on it, repack the wheel bearings, and you're probably good to go. If the old DuraTorque is pretty flat, minimize the load in the trailer and take it easy.
The rule of thumb is that the trailing arms should angle down a little from the torsion tube with the trailer at towing weight. Level is marginal and an up-angle means the axle is ready for replacement.
For what it's worth, the DuraTorque in our 1960
Pacer was fine when we got it. The torsion bar was a little tired, but the brakes looked almost good as new and the wheel bearings were full of grease. We replaced the axle on general principles after a year of camping. Raised the ride height several inches when we did--had to change the hitch height!
Good luck with your new trailer!
See you down the road,