Looking for replacement part

I had purchased some parts for some Certainteed windows which you had in stock. I am also looking for some parts for a window screen for the same Certainteed window. The window frame retains the screen on the sides only. The frame itself has a little channel on the sides for retention. The screen frame has mitered corners. I am looking for the corners for this type of frame. They are L-shaped cast metal, approx 1.5-2" x 1.5-2" for the L shape, with the piece approx 0.23" x 0.125" thickness. The cavity is approx 1/4" x 1/8" and the corner piece is held within the frame with two punched dimples on each side.

Right now I have not removed anything from the screen frame.