300 for sure. . You'll be able to push heavy high bc bullets at very good velocities. Sure it might be a touch overkill for hunting deer, a 6.5 would work great in that application. For elk size game or especially moose you'll be glad you have a 30.
If you don't reload I would be looking at a 300 win mag*
For a scope, I just bought the new Vortex Razor HD LHT 3-15x42. I believe it's the best hunting scope Vortex has made yet. Upgraded from one Razor to the next.