sounds like to me your looking for a gun similar to this package....

http://www.hunt4ever.com/shopexd.asp?id=101646

This gun comes with a regular smoothbore barrel and a fully rifled barrel with sights. Since you want a scope the only drawback to this package would be having to take the scope off when not needed. If your wanting a more versatile gun then find a shotgun with a cantaliver scope mount that way when you take the barrel off the scope comes with it.. then you can just throw on a smoothebore barrel. Taking the scope off on a regular basis could be a pain if mounted on a saddle mount, but if just put on and taken off once a year for deer season it wouldn't be too bad.

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