Searching for Stanley window plastic roller

Hello,

Your photos appear to be showing part of the pulley system of a channel balance. Unfortunately, these parts are not available separately and we do not recommend trying to repair these balances once they are damaged since  they are under a lot of tension. We should still be able to help but we would need to see an undamaged version of your channel balance from the other side of the window. Make sure to show both ends, the stamp code on the metal channel, as well as the clip at the end of the pulley cord. Thank you!