aluminum glazing

Hello,

I need to replace two 11.25"x 12" window panes in an aluminum frame. It's a 25 yr old frame, I don't know the manufacturer, and can't find snap-in glazing for it anywhere -- Hoping you can help! Attached is picture of original aluminum glazing.

The short side that snaps into the frame is 3/8" wide, with a 1/8" lip. The wide part that holds the glass in is 3/4" wide.

I'd prefer white aluminum like the original, but suppose white plastic would work -- Do you have anything that will work?