Ithaca:
In my estimation your Scott is probably original. I have a number of them in both hammer and hammerless forms. None of them have concise barrel lengths. All vary about 1/4 to 1/2 inch. This is typical for many English guns. It doesn't mean they've been cut (do the tubes "kiss" at the muzzle?). Also, Scott chokes are often as observed -- tapered. But Scott would make anything you wanted. Including parallel chokes. Finally, .030 of choke is fairly the threshold of "full" by UK standards. I wouldn't worry about that either. It should bash anything you fire it at. Just use 1 oz. 1200 fps or less loads -- if you can find them in the States.

Best, Kensal