Cutting a shotgun barrel is about like cutting a section of pipe.... just need to keep it square, and smooth the rough edge with a bit of fine sandpaper (like 400/600 grit).

The bead... if you want one... is more tricky, only because the placement is the key to making it look right when you're done. There is a jig for that from B-Square (and others) or if the smithy has a XY table on his drill press (or Bridgeport), then he can just indicate the barrel to get it centered (with his Interapid dial indicator). He'll still need to keep it "square" with things - which I'd do by assembling the barrel on the action, barrel in the vice and square against the action - which is doable with the long table on a mill, not on a drill press.

I cant see that costing more than $50, and probably much less. Its an easy thing to do really, and takes almost as much time to describe as do.