Also any advice in general about Mini 14's as I've never even touched one before last night.
I've had a Mini-14 ranch rifle for six years now. My advice would be to keep the current stock and save your money for ammo and/or a scope. Recoil is VERY mild and shouldn't be an issue for your son. Some of the pre-2007 production runs had mediocre accuracy that can be improved through installing an Accu-strut, which doesn't detract from the rifle's appearance.