Window metal clip replacement

I am afraid we do not offer an exact replacement. Our two best options are our 70-204 and 70-004. The 70-204 is a slip-on latch is pushed onto the bottom of the screen frame and the latch loop hook slips over the ball-head screw. The 70-004 installs in the spline itself. Look over both pieces and see if you can modify one of these to work on your window. 

I'm afraid I'm not familiar with the part you're diagram represents. Would it be possible to see a photo of the part itself? That may help point us in the right direction.