Identify which part

Hello, thank you for posting,

We can supply replacements for your original balance, but to further review, are you able to confirm the depth of the shoe as shown in the diagram below? 

Can you also confirm that the weight of the window sash weighs 38 pounds? The sash will need to be removed and placed on a bathroom scale. From there we can determine the correct series and stamp option for your window. 

Comparison of the S378, S380 and S385 balance shoes.

Thank you for confirming,

Please see the S380-30 channel balance as a replacement. For a 39 pound sash, you can either use a 2965 or 2970 stamp option as either can support the weight of the sash. Please let me know if you have any additional questions!