If you've got a RED Digital Cinema Camera and you need spare top or bottom flags for the RED Matte Box, you can make your own using these templates.
Use the files to laser-cut or mill whatever materials you want to use. I've laser-cut black art board, but you could probably mill a thin sheet of metal or various plastics. It's best to keep it under 3mm thick so it'll fit properly in the mounting screws. (No CNC machine? You could cut this by hand if you're good with an X-ACTO knife!)