It's time for a pistol

S&W 44 magnum fits the bill. .45 long Colt, .45 ACP, 38 Special .357 Magnum, etc...

Up north we have similar requirements for "short range weapons only" hunts. Typically in the developed farmland areas.

Personally, I'd go looking for a rifled slug barrel for your 12ga or remove your choke and use a saboted slug.