Window balance

Hello there. Unfortunately it does not. We will need to see the balance removed from the window, with any stamps and end attachments photographed. From there we should be able to begin to narrow this down. This blog article here covers everything we'll need to know about the different balances you may need. 

Thank you. This appears to be the top end, where the screw tab extends from the channel on a cord and presumably screws into the window track. Is that accurate?

This is very helpful, but there's still the other end to consider. That determines how the balance connects to the sash, which is equally as important. This is usually done via some kind of shoe.  You said that you don't see a plastic end, which means it either broke off, fell off, or is otherwise missing. That's a problem. Without it, we can't proceed. 

Your next step should be to check an identical window in the house that might have all its hardware remaining. We can use that as a reference, if you have one. Otherwise I can't give you a recommendation.

I'm not sure I understand. The photo above only shows me one end of the balance. We need to see the other end as well as whatever pivot shoe, bracket, clip, or whatever else connects the balance to the sash at the bottom.

In other words, right now we don't have enough information to proceed. The only way we can move forward is if you remove an undamaged balance from the window and show me every relevant component. That should be your next step before you do anything else. If that's not possible, then I am sorry to say that we will not be able to help you find a replacement balance for your window.