Question about a replacement tilt window pivot lock

I have some older replacement windows (maybe even 20-30 years?), and one of them now has a broken pivot lock shoe (see attached photos) on the left interior window. There are two flat springs behind the lip of the channel to the left, and as you hopefully can see, the cam is broken on the left side. There are no vinyl cutouts anywhere on the track for removal and replacement. The springs are fine, just the cam is broken. I can get by with it as is (I can still open and close the window), but would like it to work properly. Any suggestions?

Thanks very much for any guidance you can provide.