I bought some 5" x 7" aluminum roof flashing at Home depot. 10 pieces for $3. I'm pretty sure I can bend it up and paint it, in about 2 hours, all for less than $10. The original plastic pieces are nothing that special.
Hmmm.....
Can I hire you to make me some aluminum tread plate door sill protectors for me by chance? I've bought a 2'x2' sheet of thin alum tread plate (.032" thick)....but I think it's likely beyond my skill level....