Broken Shoe spring retainers

I've never seen a design like this before and not sure yet how to disassemble. The sashes sit in a vinyl tracks that fully conceal the spring and shoe. To remove the sashes you have to push the right and left tracks in towards the wall to pivot the window, no levers or buttons. Then tilt the window like other models and lift one side to remove. It looks to be a very simple but odd design. The shoe is very small and slender with what looks like two pivot holes and a hook for the long spring. They are made of plastic and the spring hooks have broken.

Because these have a unique design I've never seen with the sash track needing pushed to release the sash we do not want to attempt to remove any components untill we can identify that parts may be available as both sashes will need removed and the brittle plastic/vinyl sash tracks removed to view the springs and shoes. It looks as if it might be all one assembly on both sides. We need an expert to help identify this design.