Coil Balance
Thanks for writing in! We do not have a replacement match for your coils, so you'll need to replace the entire assembly. The shoe can be replaced with the 15-177 Coil Balance Shoe. To confirm that it will be a fit, carefully review the dimensions below and compare them.
The compatible coil spring is the 1/2" wide Series 152 Coil Balance. They attach to the shoe using the 33-072 Screw. To determine the springs needed, you'll need to search for a stamp/marking on the coil. If there aren't any, you'll need to confirm the exact weight of the window sash. Take a look at the video tutorial below for instructions.
The cover used for this spring is the 15-143 Coil Bushing, 15-144 Coil Bushing Cap, and 15-145 Coil Support Barrel, which all snap together.