Basically, the drawbacks to having multiple sets of variables are readability, performance, and ease of updating. *gosub and various other methods could improve on any or all of these sometimes, but choicescript games have a massive safety margin for performance, this case is pretty straightforwardly readable, and no updates are expected, so I’d recommend against using them.
Simple number of variables is not really going to be an issue here; if you wanted to do a Prince Of Persia thing and let people go back some number of choices whenever and thus needed a save point after literally every choice then it might start mattering. And a copy-paste plus swapping numbers is all the effort that will be required to create them so that’s probably easier than using gosub.
I might use gosub to have a centralized load routine, but it’s not really necessary and I wouldn’t recommend it unless already comfortable with using it. You could almost certainly do it in fewer lines of code but it would be harder to follow per line.