If you can't find a loaner, maybe she could rent:

http://www.machineryrowbicycles.com

We rented road bikes recently on our trip to Utah. I was really nervous about fit and the quality of the bike, but was pleasantly surprised. I think we'll be more open to it from here on out. We did bring our own pedals and, if I had to do it again, I'd bring my own saddle, too.