Certain Teed Shoe and Pivot Bar
Looks like you have the old Simonton brand coil balance assembly. They no longer make this, but we have two possible solutions for you to consider.
The first is our 15-192 pivot shoe, along with our Series 170 coil spring (and other parts related to its store page). If I understand your post correctly, it seems you're already considering these. They're not the right brand but I have had customers in the past tell me that they got it to work after grinding down the front of the face, which sticks out just a little too far for this window.
The other option is a more modern replacement that I think works just as well, if not better, since it's not prone to breaking in half like your old one is. The video below will go into more detail. This will explain exactly what parts you need to buy and how you can install them in your window. Just note that you will need the exact weight of your sash on hand in order to calculate the proper spring strength. You want to divide that weight by how many springs support the sash, then pick accordingly.
