Sash cord springs for Malta pivot windows

I have successfully repaired several Malta tilt in windows in my house simply by replacing the broken plastic Malta pivot shoes. There are a couple of windows which need a different approach since it appears that the counterweights or spring weights or whatever is supposed to tension the sash cords are broken. I've attached three pictures of the window: 

1) top of the window/track with no apparent access points, 

2) bottom of the window/track, again with no apparent access to the springs, and 

3) middle of the track showing the exposed sash cord (note that there are no obvious track springs, just bare cords)

How do I get to the weights so that I can identify the problem and needed replacement parts? Thanks for any suggestions.

The jamb liners can be removed. Remove the screen. You must remove both sashes by opening the windows top and bottom and tilting them as if to clean. Remove the sashes by tilting the down on left, up in right, or visa versa, and removing the shoes from the tilt pin (if not already broken) part 5-159 shoe replaces. Once sashes are out, use a stiff flat blade Putty knife or wide blade screw driver to pry gently from wood toward plastic jamb liner on inside or outside interface between these two components. Start at the bottom of the window. The jamb liners are held in by a 1/4" lip on both sides. Like a hat brim. Once the bottom is started, move up the liner to the top. The top is captive in the top frame. You must now angle the liner across the window at the bottom to remove the top, pull down as you do this. You should now have the plastic jamb liner removed. You now can access the bottom spring clip, plastic piece which usually breaks and top shoe, also piece which breaks. In my Malta 1992 vintage windows this is the case. I am looking now for replacement ideas for the two pieces. Or Swisco to manufacture some new ones or replacement components, please? See attached photos.

Pictures of pieces needed and dimension shots.

Lower spring attachment pieces

More photos

I can supply pieces needed if you can re-engineer replacements. Likely many Malta customers looking for the same items.