Again, +1 to the requests for location and duration of your trip, and expected unfriendlies in the area. If you're going where you have the possibility of encountering moose(moose are far more dangerous to humans than brown bears) or brown bears, then I will second the Marlin Guide Gun in Stainless and .45/70. A Marlin .45/70 with the right loads and ranges has taken every land animal on this planet with aplumb, including elephants. With normal loads, it can also put lead on target quite fast.
As far as carrying a handgun, first, what handguns do you own and shoot well now, find out if it's legal to carry where you're going, then determine what dangers you'll face on the trip. If you've never shot a handgun before, you'll need some training to become proficient before you can use it effectively for defense. If you do shoot now, what do you shoot? Revolver or Auto, brand and model? You may already have something that will work, a .357 magnum has successfully hunted all game in North America, and will do the job if you do yours. Does this mean that it's sufficient for moose or large bears? No, but if the likelyhood of running into those animals is low to none, I'd say it's fine, same goes for 10mm in an auto.
If you don't own any handguns, and/or have little experience with them, and you face the possibility of large bears, etc. I'll suggest, IMHO, the perfect, only own 1 handgun, handgun, the .44 magnum, preferably by Smith and Wesson. I'd go with a 3-4" barrel, a good holster or fanny pack holster, and since you're near water, stainless steel. If you've never shot a handgun before, you may be intimidated by the .44 magnum, and many will say it's way too much gun for a person to learn to shoot with. They'll say start with a .22 and work your way up, well that's fine if you plan on starting a gun collection, or are interested in becoming the next Bill Jordan, but a full size, steel .44 magnum loaded with light .44 specials is akin to a lightweight .22in felt recoil, and even a lightweight .44 Mag with lightly loaded .44 specials is easy enough to learn to shoot with. Your selection of ammo with the .44 mag is infinite as well, from beyond spec power, hard cast beast killers, to .44 special shot shells for snakes and other pests. I would go loaded with a cylinder full of the hottest flat nose rounds that you and your gun can handle and shoot accurately. I'd carry a 1 reload of that ammo, plus 1 speedloader of .44 spec SWC's for small game or two legged predators, and 1 load of shotshells for the really small stuff(which in a survival situation may be all you see to hunt and eat). This loadout can be adjusted to your conditions, and threats. In AK, I'd probably skip the shotshells and add an additional load of mags. In Arizona, I might go with a lighter loaded magnum and add a some .44 special hollowpoints for the 2 legged beasts.
Whatever you decide on, shoot it alot before you go, and train to snap shoot as though an attacker(beast or being) is charging you. You won't have time to set up shooting sticks, or draw a long bead on your target. In the words of Col. Cooper, "front sight, press" meaning focus on the front sight after presenting the piece, and press the trigger.
