B/C you mentioned handing down to the son when he's ready, I'd advise the 7mm/08 as it will be about the best combination of effective killing potency combined with easy recoil. The Creedmore is wonderful too, but finding the ammo easily could be a challenge .. much more so than the 7mm/08. My second pick would be the 308.

I can see your son starting out with such a rifle and keeping it his entire life, ... just because!

My pick is the Howa. But you might end up a bit higher than $600.00 depending on the scope you choose.