Think used, a lot of good quality rifles many with decent scopes can be bought today at half the price of even the new budget stuff.
Being new I am guessing not a hand loader so I rule out the 260 Remington unless he is affluent and can pay that kind of money for ammo.
243/6mm/244 easy on the shoulder and ammo fairly easy to find for the 243. Good for a whole list of North American game.
308/30-06 ammo fairly easy to find and good for any north American game except maybe some of the big bears.
I like my 7mm08's but to walk into any north country store in Michigan you may not be able to buy ammo for it like the 243,308or 30-06.

Al