You could take a SxS with screw chokes, choose a rifled choke tube (pair), install them, then re-regulate the gun to hit point of aim with the screw chokes.
I doubt it would pattern with smooth chokes and shot exactly as it had beforehand, but you can give it a try.

A great deal of the challenge is to get properly regulated rifle and shotgun performance out of the same gun.
My gut says it isn't easy.
The 'few and far between' nature of properly running 'paradox'-style guns in existence tends to support the gut feeling.

If you go ahead with the project, let us know how it goes!

Cheers
Tinker