Honestly, you need to know more information regarding the gun before giving this fellow who owns the Ithaca a bunch of regurgitated baloney. What grade is the gun? Which patent action Ithaca is it? NID? Crass? Flues? What's the overall condition? If it's a fairly common gun, a non collectors piece, or something not too special, why not suggest opening the chokes to suit his needs? If it's a rare and highly collectible gun, what's wrong with suggesting selling the gun and buying something more useable? The suggestion of using spreaders is ok...for some guns. In others, they just don't work that great.
Just because the gun is a Ithaca with Damascus barrels doesn't exclude it from simple modifications that can make it more user friendly & practical.
