Don't worry about it! Any of the cartridges mentioned above will do a fine job on deer size game if you do your part (proper shot placement with good ammo). The 7mm-08 and .308 are excellent short action cartridges. The .270, 7mm Mauser (7x57), 280 Remington, or 30-06 are all good standard rounds to use. Ammo is readily availabe for all. The 7mm Mauser selection of ammo may be limited in factory loads, but it's a good
round for those who "roll" their own.
Shop around. Try out your friends' guns. Pick the rifle, in any of these cartridges, that
fits you best, that you like, and fits your budget. Savage is good, so is Remington,
Ruger & Winchester.
By the way, any of the above cartridges will also handle black bear, and even Elk in most cases.