window frame corner piece

To: Swisco.com

I'm trying to find a replacement part for a metal corner piece in the aluminum window frame provided in this picture. This metal piece holds the frame at the bottom corner, one on the left and another on the right bottom side. Each aluminum frame corner has two holes on each side where this corner piece is inserted. If your online store doesn't carry this piece can you assist me with information where I could purchase this part?

Thanks,
S. Davis

Thanks for the information on SWISCO part 20-012. What type of screws are needed and does it also require screw nut to secure it? Does your company carry the screws for part 20-012?