Cranks and balances

Hello,

Take a look and compare the 15-129 pivot shoe, 26-040 pivot bar, and 39-220B to your original hardware. The diagram that you included shows another operator that resembles the 39-002. 

I suspect that your balance may be a match to the S770 channel balance but we would need to see a photo of the metal clip at the end of the pulley cord to confirm. Thank you!