They are big into rescuing factory hens in the UK. Every site I look up is in the UK. Little red hen rescue and Chicken trust actually seek out factories and buy the spent hens from the farmers and then adopt them out.
Too bad we over here in the USA arent as motivated.
Maybe you can find out where your states local egg farmer's are and ask them personally if you can take one or a few hens off their hands when the time comes....
Sounds corny and 'overboard' to some I suppose, but hey, its worth it if it changes at least one life from winding up as dog kibble or a pot pie. That's gratitude I guess....
Good luck on your mission. Maybe someone will have more info...