finding replacement parts for Alside Ultramaxx Window

Hello - I am writing on behalf of my mother in law. She has some Alside windows that were installed 20 years ago (120-417493). On the window, there are the spiral pieces that come down each side. In one of them the spiral has come off from its attachment because the base (pivot shoe) part of it that attaches to the bottom of window that allows it to rotate out when trying to clean the outside. We are trying to figure out how to fix these parts and which replacement parts are needed. Can you provide some guidance? Thank you!