PGT window size 18W x 23H single hung.

Thanks for posting. If I follow, it sounds like you need a new channel balance. The balance is what regulates the window's movement. Unfortunately that stamp only tells us the balance's strength. It does not tell us its identity. You'll need to remove the balance from the window and give us specific photos for us to determine what you need. The videos below explain what we're looking for, as well as how to remove and replace the balance. Let me know if you have further questions. 

Thanks! This balance looks like a match for our S395-12. This comes with a 19-005 top and 15-001 bottom nylon fitting, so as long as those two match up then you should be good to go.

I don't believe that top sash guide is our 18-009, the design is a little too different. We actually don't appear to have an identical match, but of all the parts we carry I would say that the 18-015 is closest. This also happens to be made for PGT windows, so that's promising. Your next step is to review our dimensions to determine how well they match up. If they align then I think it's worth trying.

I'm not sure I understand your second question. All of our balances have plastic end parts. Can you clarify what you mean?

Alternate view of 18-015

Alternate view of 18-015