Not sure what Channel Balance I need
Thanks for writing in! The S380-27 and the S385-27 are great contenders for a replacement, but that will depend on the shoe depth and exactly how it is configured. There are also a few other possible replacement options.
To confirm which balance you need, I'll need just one more photo. May I see a photo of the pulley system in the center of the balance? There is where the spring and the string meet in the middle.
For an idea on how to confirm the depth of your shoe, take a look at the diagram below.
Since the measurement appears to be over 1", you'll need the S385-27 channel balance.
You'll need to select the 2640 stamp option.