Cut it off?? Are you kidding? An Ithaca 37 w/ a polychoke & you want to cut it off? Or cut it off & send the bbl to Briley? For what? For them to put the chokes you cut off on the inside of the bbl? You know how many choke options there are on those polychokes? You'd need another big pocket just to carry all the choke tubes.
Dont buy that gun. Let someone find it who would appreciate what a great gun it is, just like it is.