You will run out of good deer country before you can get far enough north to afford land. Someone doesn't live on that land for a reason. But there are many unpopulated and undeveloped townships both sides of Hwy 17 across the top of the province.
In my experience in Ontario, when there is a large block of undeveloped land, someone else has already got long established hunting privileges. There is a sense of entitlement that transcends changes of ownership or commercial use. The usual excuse runs something like, 'Oh we've been hunting here for years. Old Bill told us we could hunt here forever, and he'd make sure no one else had permission. We don't bother anyone.' Well, old Bill is long dead and squatters rights don't apply. If someone new bought that cedar swamp, black spruce thicket, and granite ridges, they are quite right to remove any trespassers. But tell that to a crew of guys who've been coming there for two generations. Posting signs, tearing down cabins, building fences, and otherwise preventing access is a fast way to have your own house burnt down.