Window channel balance

Hello there. That stamp is not an identifier; it just tells us the balance's strength. Without seeing the attachments on both ends, I am only guessing, but is the top attachment the 19-005? If so, and if you are certain the shoe depth is 1-3/32" (it must be measured as shown below, and can really only be reliably done with the balance removed from the window), then you need an S385-30 Channel Balance with a stamp option of 2930. Be sure to double-check all these points before proceeding.

Comparison of the S378, S380 and S385 balance shoes.