Thanks for posting! I am confident we can make a replacement recommendation for your coil balance assembly but I'll need to see a photo of the entire assembly removed form the window to identify the right replacement. I'll also need to know the measurement for the width of the coil.
Please don't hesitate to reach out with any questions you might have.
Thanks for confirming this information. I believe you may need a 3lb coil but I wouldn't be able to determine that with certainty based on the stamp. Are all three coils stamped with a #31?
Also, may I please see a photo of the compatible shoe? I'll need to see this to confirm the correct replacement replacement for your balance assembly.
Thanks for the photo. Your coil balance spring can be replaced with the Series 196 Coil Balance. Since two out of three of them are stamped with a 3.1 or 3.5 (respectively), I believe you'll need the S196-3. You'll need to double check that the third coil is also stamped with a 3.
This coil spring is compatible with the 15-263 Titan Coil balance Pivot Shoe and the 15-261 Titan Triple Support.
If the shoe and the cover are still in good condition, then yes. However, you will ultimately need to make that determination.
I hope this helps!