Given the spotty supply of brass, bullets, powders, I would go with the .308 Winchester. since you like the short action.
while it may not have the knock-down of larger cartridges like the 300 Win mag, or 338, it is more than adequate for either animal.
I have spent a lot of time in northern Canada (Yukon and NWT) and I have seen more 303's and 270's being used for moose than any other cartridges. Certainly anything those will do the .308 Winchester will do as well. But being Canadian you are probably aware of that anyway so I am preaching to the choir.
drover
