Dusty Stevens
Shiner
This and a 2x72” knife grinder is the answer to finish sanding. Financing is available by the way.Go and have a look on practical machinist gunsmithing forum there is a thread on profiling barrels. A lot of BS but some good info and photo of a follower in amongst it.
Be prepared that you might need to do some linishing, sanding while the barrel is in your lathe as that's what a lot of barrel makers do. If you don't want sanding grit on or around your lathe then send it out.

BARREL SPINNER | Brownells
For many years gunmakers have been polishing barrels using a barrel spinner made from cast aluminum. These work great, but with commercial use the brittle castings are prone to cracking. These cassettes are 100% CNC machined from billet 6061 T6 ba...