So, to clarify, you have a plain (non-ribbed) barrel now and you want to add a vent rib to it with a bead front?
If so, I suppose you could pay a gunsmith to do just about anything including soldering a VR on a barrel that doesn't have one, but you'd pay dearly for it.
You'd be better off buying a new barrel and selling the one you currently have to recoup some of the cost. You could also probably find a used barrel that would meet your needs for less $.