Check out the Parker line of crossbows. I would look at the Ambusher and Challenger II models. Both are for female/youth sized shooters. The Ambusher has an adjustable stock and draw weight. This helps smaller framed shooter.
Budget? Can she **** one with a rope cocker or will a crank cocker be required? If not sure, you may want to have her try to **** a crossbow with a rope at a box store to see is that will work or not.
How about can she get it cocked with a rope type?Is a crank type cocker needed?Does the store have a range to discharge a cocked crossbow?If used in that context I would not have a problem.You won't either.