200-400 USD
Yes, but would be better if you put in an improved cylinder choke.
Try the U.S. Patent Office
If it is a stock gun it probably has a open cylinder unless someone has added a choke.
Pattern is dictated by the amount of choke on the barrel(s)
Unless it is a full choke, the answer is generally yes.
Try the receiver once separated.
200-600
200-300 USD.
corson barrels.com
50-250 usd
50-850 usd