Need to replace these parts
Thanks for reaching out! We used to recommend our 15-192 Certainteed pivot shoe to replace your Simonton brand part but to install these, you'll need to be sure to shave down the aligners so they will fit in the window channel. These would use the S170-406 coil spring for the bottom and the S171-405 coil balance spring on top of that coil.
Your pivot bar appears to be part 26-336. Look over the dimensions to confirm that this is the correct fit.
You may also want to consider the 15-259 pivot shoe, which should fit well in the track, along with the S159 coils springs and 15-255 single or 15-256 double support. To use this assembly, the original pivot bars would need to be replaced with our 26-083. We are still in the early stages of confirming if this replacement is a good long-term solution but we have high hopes that it will work with little need for modifications, if any. Take a look and if you decide to give it a try, we'd be eager to hear how it works out for you.