Someone may have mentioned it earlier, but with the 10-round limit, what about an sks carbine? Top-loading's not ideal (unless you're talking to a rabid Garand-ophile), but the price of the gun & ammo both would lend themselves to obtaining more training, more practice, and more depth of stocked supplies. You'd get maximum capacity, plenty of power, as cheap a defensive caliber as you're going to find, and a gun/caliber that would work for the feral hogs as well.
"I don't need a thousand dollar shotgun. I need to know how to run the shotgun I got." - Clint Smith