Manitoba, Saskatchewan and Alberta have good colour phase and for the most part average sized boars (Honest 6-6.6' 300 + LBS range). Generally the more remote the better odds at connecting with the larger boars. I can only really speak of Saskatchewan in this regard but bears are really under utilized in terms of hunting opportunity, 90% of the guys here hunt for a rug and thats it, very few eat the bears so the resident hunters who actually harvest bear is pretty low in comparison to the resource. As such the bulk of our annual harvest here is produced by americans through outfitting and at that isn't really denting the population either. Most outfitters produce numerous bear sightings over bait each time on stand(of course weather is a big factor). I am sure the same can be said of my neighbouring provinces to the East and West. A bonus to Alberta is the ability to buy 2 tags, so that might be of interest to you.

For truly big black bears I agree BC would be the best place. Vancouver Island is pretty much the meca for Canada in terms of huge blackie's.

Check out the provinces Outfitter websites in which you may be interested in hunting. They will give you info and directory to the outfitters themselves.