My view is that you better buy a 505 for her.
She will not have to spend money on books again.
300 bucks will not make you bankrupt.
She can repay from the money she saves on not buying books.
When I was 16 I wanted something very bad and my parents didn't bought to me.
Now I can buy whatever I want, but can't be happy, cuz I still have the memory not getting what I wanted when I needed. I can not trust other people, I can't believe that somebody can be nice to me if my parents weren't.
Of course you need to be realistic, but she didn't ask for a Lamborghini.
This age is defining in my view.