I have included a picture of the channel in which the balance lives, and a picture of the shoe as it is installed. Sorry I cannot get a better picture of the original shoe. The shoe is broken in the balance I removed from the jamb, and I don't want to try to remove the other side because it was such a PITA to get the one channel out of jamb. The shoe does have the little metal knife blade on a pivot, but I cannot be certain it is exactly like the 15-014.
The dimensions of the channel seem to match up with the dimensions of the 15-014 show. Please refer to my picture of the channel.
Hopefully this will be enough information to identify the properly replacement channel balance. If I need to remove an original shoe I think I may need to cut out a small section of the channel to get it out, or find a tool to spread the channel open.model. Only one is broken, but I would consider purchasing 2 (or more).

