Need Replacement Top Sash Guide Used With S385 Balances

This sash guide in the pictures has deformed and broke. The guide is screwed with a single screw into the top of the channels on both sides of our single hung windows (only the bottom window goes up and down) and this sash guide holds the window balance in place at the top of the moving window. The angled part of the guide is on the bottom and the little hollow cube is at the top of the guide. All of our window balances use 1/2-inch wide S385 balances of various lengths and strengths based on window weights. On a few windows, this sash guide at the top of the window has failed like the one shown in the attached photos where the top of this plastic sash guide has deformed and broke far enough that the the window balance came out of the window and went all the way to the top of the window frame. We need to replace these sash guides to keep our window balances in place without shooting up to the top of the window frame. Can you let us know what part will work to replace this sash guide?