I would go with a 7mm/08. I have a model seven youth in 7mm/08. My cousins boy been using his model seven in 7mm/08 for the past 3 years and haven't had a problem killed a hand full of dear and a bear with it. My model seven will be used by my 8 year old nephew next year. I will use my current load of rem 140 grain corelocks in it for him. My cousins son or his 243, 6mm and 7mm/08 and liked the 7mm/08 the best he uses 139 hornady sst. I feel the recoil is not noticeable more in a 7mm/08 then a 243. Remington also makes a managed recoil load in 7mm/08.
http://remington.com/products/ammuni...ed-recoil.aspx