Man, that sucks. 00 buck would over penetrate as well, as it's still moving pretty close to the same velocity as a 12 gauge, just less shot. I don't have enough experience with a 410 to be of much more help. All i know is I pegged a few squirrels with 4 shot/410 when i was younger, and I'm not sure it would do a whole lot more than really piss off a BG. He might be pretty messed up but i don't think it would stop him in his tracks which is the primary concern, especially if he had any jacket of any thickness on.
I have maybe a couple more suggestions. A beretta storm maybe. I don't know how your state/city lists this weapon, but it's a fine HD gun. Worst case scenario maybe you could block off a mag to 5 rounds. I would feel much better with 5 shots of 9mm +P, .40 sw, or .45acp in a semi auto platform than a 410 with birdshot. Again, OP is a concern, but only if you miss
If maybe you could find some HeviShot loaded shells for the 410, that would give you a little more umph as well, but i don't know if they make that. For my home defense, i have an AR primarily, and then the benelli SBE with 00 buck. If i run out of those, I will start throwing 3.5" Hevishot goose loads, lol. I have no concerns of OP though, so the BG better get OUT cause there will be all kinds of rounds going through the walls, and floor, or wherever I think he could be
Is there any reason that a handgun wouldn't suffice?
If it's just a city law, the worst punishment they can dish out is a misdemeanor. I personally would risk a misdemeanor for the sake of personal protection, but thats just me.