Don't know about the youth stock, but I would call T/C, as they might sell them direct to you. As far as calibers for deer are concerned, I would consider the folllowing:
30-30
7-30 Waters
6.8mm SPC
I bought mine in 30-30, in part for when the little ones are ready to hunt, in part because I was tired of being belted every time I pulled the trigger on my 7mm Rem. mag. I picked the 30-30 over the others because it was all I could find at the time. If all three were sitting on the rack side by side, I would have to draw straws for which one came home.
I'm guessing the 30-30 is the hardest kicker of these three, but others could tell you better about that than I. At any rate, it is very comfortable to shoot.
I hope this helps.
Regards,
Mike