If you shop around at gun shows you should be able to pick up a new 1100 "Synthetic" for about $400. It is a 2 3/4" chamber, 28" barrel gun. This should be able to do anything you want either playing games or for defensive ourposes. If you want a 3" chamber you'll have to spend a lot more money for the "express or an 11-87. The "Express" will not reliably handle light target loads. The 11-87 won't either no matter what the ads say. Have a 'smith cut the barrel to whatever length you want and he should be able to bore and thread it for choke tubes. I had mine cut to 21" and threaded for "WinChoke" tubes as they are easier to find in store and cheaper.
I have found mine to be very reliable with good ammunition.
I hope this helps.
I'm not saying the 1100 is the best thing since sliced bread, but it'll do.