Met another gearhead on a flight recently. I had my Mopar Engine Building book out and that started the conversation. Eventually we got to talking driveshafts, and this guy worked for Dana many years. I said in the Green Bay area we have Machine Services and he knew them well. He also said Denny's Driveshafts is the place to go for anything you need in a custom driveshaft.

https://www.dennysdriveshaft.com/

denny's has a very good reputation as i understand it.
i got a new drive shaft for my charger this year from Action Machine.
it fit like a charm, the workmanship looks very good, and was reasonably priced. [i thought]
fast turnaround as well.
i haven't had a chance to try it out yet, as the car is still up in the air on stands.