In terms of modern, semi-auto firearms I think we'd be fine. However, a total import ban would eliminate Uberti and Pietta, who make most of the cowboy six-gun clones -- including not only their own brands but also Cimmaron, Taylor's, and I think a couple of others. IIt would also put VTI Gun Parts out of business.
----Which is why I would be a little suspicious of this. I don't think President Ponysoldier gives a tinker's BLEEP about repro cap & ball and black powder guns.
I have no doubt he'll issue a EO banning importation of some guns and related stuff.
Right now, I'm going to wait and see.