Help in identifying the channel balance

I believe you have the old discontinued Silverline Swinger window. They used a special kind of asymmetrical balance system. The way they're setup is a little complicated, so I'll try to be as clear as possible.

Typically, the balance on one side has the 19-008 cap attached at the top of the balance and the 15-025 shoe attached to the bottom. However, the other side has only the 19-008; it does not have the bottom shoe at all.

Furthermore, each balance should have a different number stamped on the metal channel. You mention that one balance has 2540, but I'm not sure which balance that applies to; the one that has both the 19-008 and 15-025, or the one that only has the 19-008 by itself.

Would you be able to look over your hardware and confirm for me what you need? These need to be custom made, as we assemble them here, so it's important that we know exactly what you have. Thanks!