Check out these ones on dogfunk.com. If it says "Women's" and "EPS", it should be fine. You can check each helmet's safety certifications in the column on the right side of its page.
These are also cheaper than the ones on evo.com, and Dogfunk has a much better lifetime return policy. If she does get one and it doesn't fit, you can exchange it for free. If you need a refund, play it nice and they'll always give you the return label for free.
They also have a load of other brands to choose from.