Basic...
I'd look at two different pump shotguns... the Remington 870 and the Mossberg 500... BOTH with TWO (2) barrels each.
The first barrel... a standard 28" shotgun barrel with a ventilated rib and inter-changable choke tubes.
The second barrel... a short, rifled (slug) barrel with iron (rifle) sights and the barrel set up for mounting a low powered scope.
Both are good shotguns... the Remington is supposedly better quality, but I've never heard anything "bad" about the Mossberg's quality... and I believe the Mossberg may be a better "value"... depending on the price difference between the two shotguns.
I've heard Mossberg's Customer Service is excellent. By the same token, I've heard that Remington's Customer Service leaves something to be desired. But I've not had any personal experience with either one.
I like the location of the safety on the Mossberg (on the tang right where it should be, in my opinion)... but that may not be too important to you.
Mount a 1x-4x or a 1.5x to 5x variable scope on the rifled barrel and sight it "in" 2 inches high at 100 yards... this should give you a point-blank-range of about 125 yards.
Here's 2 Mossberg models that you might like:
#54243 12 ga. Trophy Slugster COMBO, includes all the features of our Dual-Comb® Trophy Slugster #54232 shown above, plus an additional
28" ported VR barrel w/ Improved Cylinder, Modified and Full Accu-Choke tubes. MSRP $379
#52264 12 ga. COMBO Mossy Oak New Break-Up camo finish, synthetic stock, ported 24" Rifled barrel w/ rifle sights and a 12 ga. 28" VR field Accu-Choke field barrel w/ 3 choke tubes. ...MSRP $404
See these two guns (and others) at:
http://www.mossberg.com/A sabot hollow point slug fired through a rifled shotgun barrel using a scope set on it's highest magnification (4x or 5x) should be reasonably accurate out to about 125 yards.
If you're stalking (aka "still hunting") slowly through the woods, keep the scope set on it's lowest power setting (1x-1.5x) in case you "jump" a big buck.
You might check out the local pawn shops for either of these two fine shotguns... you could save $100 or more over buying a new gun. Even if the pawn shop shotgun doesn't have the extra rifled barrel, I believe you can order JUST the rifled barrel for either gun at your local gunshop.
Strength & Honor...
Ron T.