Get a used Beeman rifle, make sure it is the German made and not the licensed Chinese junk. You're going to spend a little more, but its going to last longer, be more accurate, and thus be more fun. They can be had in .177, .20, or .22 calibers.
At that young of an age, she is going to have trouble with the break barrel action, but she will figure it out.
At that young of an age, she is going to have trouble with the break barrel action, but she will figure it out.