cockspur handles on old aluminium windows broken?

on my old aluminium windows i have several broken/missing cockspur handles. i cannot retrofit new handles as no space on the window as frame very thin.

original cockspur handles are secured using two grub screws. the screws tighten against a handle base which is a piece of metal glued into the casement. the base is basically two fingers that the handle fits over and secures using the grub screw.

cant find anywhere that sells them or a company that recognises this type of handle or window manufactureer