7x57 is good
Definitely a good choice for the smaller in stature, a hand-loaders dream (lots of good bullet choices), no need to "Hot Rod" it due to great BC and SD of .284 bullets.
Light recoil makes it easy to shoot well. I have one for my 15 year old.
A company called Zastava Arms makes a modern line of mauser design rifles in 7mm mauser but I do not know who imports them.