"unless that's the only gun you have."
It does not matter. By law if the gun has a rifled barrel it's a rifle; if it's a rimfire, it's a rimfire. You'll lose the gun, pay the fine, and be banned from hunting for years. Game wardens and the ATF are not inclined to be lenient, and it's stupid to take the chance over something like that.
As for survival, whatever you have handy is going to be the only choice, and then only when there's no supporting social infrastructure. Any other time, you fall under the scope of the law and have to take the chance.
Laws change. What used to be possible may not be any longer. The hunter needs to comply with the regulations; those that don't are a part of the reason the laws change.
Guns are cheap, it's stupid to argue that you can't afford one that meets the legal requirements. Someone earlier mentioned H&R, and two of those would be cheaper than a used 24V.