Window Spring Mechanism
The sliding up and down of the windows is controlled by spring mechanisms on both sides of the bottom window section. The spring mechanisms are held in place by a black plastic cap. See pictures.
In several of the windows, the cap has failed or broken, and raising the windows results in the spring mechanism being separated from its slot.
Can these items be replaced and or repaired? It would seem that a metal replacement cap that could be attached by a screw would solve the problem.
Thanks for posting! Your top sash guide appears to be our 18-174. To confirm that this is the correct replacement, you'll need to compare the dimensions shown on the diagram below. Although, I am confident this is the replacement you'll need. Unfortunately, there isn't a metal top sash guide that I would be able to recommend to you.
Since your top sash guides are becoming damaged, it is likely the balances need to be replaced in the window as well. If you decided to move forward with replacing the balances, I'll need to see a photo of the top and bottom attachments of the balance. I'll also need to know the stamp from the metal channel.