I have a bunch of windows in my little 1950 Cape Cod in need of re-glazing but they also need a bit of mechanical repair for their "brakes". The "brakes" hold the sill in place, they are actuated by small levers at the bottom of the sill. The "brakes" are made of hardboard or something very similar.They reside in a gap along the vertical rails of the sill and grip against the frame. Picture should help.
A) Wondering what these "brakes" are really called.
B) Hoping somebody knows company out there is making replacement parts.