There's absolutely no need for a .300 Win Mag for sheep, caribou or moose, anywhere. There is no beastie in North America a 165 or 180 grain .308 Win won't kill. Mind you, those critters are killed with .270 Win just as fast.
Suggest you lose the 2-10x40 too. 10X is far too much magnification. So is 18X for a .300Win Mag.
Where are you hunting? It matters cost wise. (Non-resident licences tend to be very expensive. Seems you need a passport now too.) A 12 day sheep horse back hunt in the Yukon runs about $22,000US plus Harvest fees of 6 grand plus 5% tax on both, for a Dall sheep, $150Cdn for a Non-resident licence, $50 for the firearms permit, $125 for the Yukon Hunter Preservation Fund(dunno, but there's 5% tax on that too) plus air fare and hotel costs. The outfitter(required in most places) will look after the carcass so you won't be carrying it out.
Do not leave anything to the last minute. Except organizing for your Canadian firearms possession permit. You can do that at the border. No handguns at all, of course.
Oh and think in terms of walking for roughly 10 days or so in coldish and wet (and the biggest meanest mosquitoes and black flies you ever saw in August)with 50 to 60 pounds on your back. Get fit before you go.
Read this.
http://www.rcmp-grc.gc.ca/cfp-pcaf/f...visite-eng.htm