Is she willing to go vintage? There are lots of lovely 531 Reynolds frames out there that are lovely.
I currently have a Gazelle Champion Mondial 531 Reynolds mixte with mavic rims, 25mm tires and cinelli drops, Brooks saddle. Got it all under 150 dollars. I've been using it for the last 6 months to really get an idea of who I am as a rider while saving money for the next bike.