What pivot lock shoe is this

The shoe you have has been discontinued but the 15-177 Coil Balance Shoe will work to replace it. The height measurement is slightly different but we are confident it will be a suitable replacement.

This uses the same Series 152 Coil Balance, attached using the 33-072 screw. To confirm the correct coils for the assemblies, you'll need to look for a stamp/marking on them. If there are none, please see the tutorial (tagged below) for instructions on selecting the correct coil weight option.

For the coil supports, you'll need the 15-143 Coil Bushing, 15-144 Coil Bushing Cap, and 15-145 Coil Support Barrel.

Alternate image for 15-177

That 'F' will translate to a 6, meaning you should be able to use the S152-6 6 pound spring.