I believe that the really hot loads for the .45 LC are only for the Blackhawk (single action) or one of the T/C single shot pistols. The Redhawk is a very strong double action, so it should handle some occasional fairly hot loads.

Hot handloads for the .45 are about the same as a .44 mag. The areas that you mentioned do not have the huge brown bears, except Alaska. Interior brown bears ("grizzly") are not as heavy as the monsters that eat salmon, but they do look huge if you are standing on the same ground that they are. Probably any large handgun of .44 mag or larger would give you the measure of protection and peace of mind that you seek.