Who rebuilds & balances driveshafts just west of Philadelphia, PA?

Next summer I'll be installing a fresh driveshaft in my E90 M3.  A new OE piece is ~$2k currently, so.... not terribly tempting.

Friend of mine has one that just needs a new U-joint.  Everything else is new.  If it's cost-effective to buy that one for a song and have the U-joint swapped out, I might go that route.  Anyone know of a place near-ish to West Chester or Phoenixville, PA that can do that work AND do a very good job balancing the driveshaft up to 9k+ RPM?  Not that I actually drive >170 mph; just trying to minimize the probability that I ever have to pull the driveshaft again while I own the car, which could be a long time.

Thanks!

I checked some notes I had from a previous car build, and there is a place in Reading I used to build a custom driveshaft nearly 10 years ago.  It was trouble free and never gave me an issue, the shop still appears to be open as well.

https://www.hartmandriveshaft.com/