I'm not normally one of those gamer geeks that fawn over "Deagles" with "cans", but I think this is one case where a silencer would be golden. Think about it: you're trying to sneak through thousands of miles of hostile territory. Sure, there are many friendly people along the way, but there are many hostile folks as well. I think silence would be golden.
Also, as late as 1650 the US was chock full of large game, including bear, elk, bison, and moose as far east as NY and Massachusetts, until settlers annihilated them as they moved west. From the Rockies westward to the Pacific, Grizzlies are your biggest threat. In the late 1700s, Jesuits of the California missions wrote of having to make long detours around groups of up to 40 grizzlies sunning themselves or eating spawning salmon in the Pajaro Valley. Your centerfire handgun, while important for defense, is necessary for large game.
A previous posters comments about swing-out cylinder revolvers being fragile in the crane and timing is right on. Also, I think that your cleaning kit would hold enough lube for 1800 shots.
Therefore, I'd have an integrally silenced Ruger Mk II and a Glock 20, with a separate silencer and aftermarket KKM or similar barrel. The Ruger would be for small game and poaching-type shots (head shots on deer at close range), and the Glock 20 for larger animals and, God forbid, defence. Should I need to shoot it out with someone, I'm saving the last round for myself. Some of the scenes in the movie "Black Robe" will illustrate why. Travelling by yourself, you'd have no one to bargain for your life if things went wrong.
-John