Look up Big Horn Armory Model 89
First thing I thought of when watching the show last night(well, maybe second after those thoughts about Phred.....). That they were just copying a model already out there. I certainly see a place for the .500 in a lever carbine tho and thought the Model 89 was it. Especially in a place like Alaska. I also have thought that along with a .500 carbine there should also be one in .460 Mag. More velocity, better trajectory, less recoil and cheaper to shoot.