In my opinion, the best semi-auto home-defense shotgun for the money is the Mossberg 930. It comes in several different configurations for home defense starting at around $600 or even less.
But it looks like the one that fits what you're looking for is the SPX version with an extended mag tube, a pic rail on the receiver, ghost ring sights, and either a normal stock or a stock with a pistol grip. The SPX should run between $700 and $800 depending on where you get it and if it has a stock with a pistol grip.
0331: "Accuracy by volume."