I'd just forget about it all, and go get her a new one in 2 weeks time if she doesn't replace it by then. I'd give 2 weeks because it means you've given her time to get money together (she may have been to the shops, but I go to the shops a lot... but it's for stuff we need like food and maybe new socks or something for school... I don't always have the money for extras we WANT but don't NEED, kwim?). 2 weeks means she's likely to get some sort of pay between now and then, and has ample time to replace it.
If she doesn't... I would try not to worry and just replace it myself.
I'd also be telling my daughter too bad for leaving her stuff behind a car, and if it happens again, she's not getting another one, but I'm a bit of a jerk parent like that. lol.