P.D.
Check with your local Lion's Club. They may have one of these devices that is used or have the ability to find one. One of their missions is "sight and sound". Your local government office will be able to tell you where the closest Lion's Club is and a contact number.
I am a retired history teacher and loved it very much. I hope you can find one of these devices for your mom. It would mean so much to her!
Best wishes to her as she continues to follow her dream!