I bought a license plate bracket (MA1068109) for my 2012 Mazda 3, but it didn't come with hardware to mount it to the bumper. Does anybody know the size of screws required to install the part? It's part number 9CD600620, but as luck would have it, my Mazda dealer doesn't have it in stock and the description isn't clear about its size. I'm sure it's something I can buy at Home Depot.

 

AFAIK a #8 by 1" sheet metal screw should work, if it's screwing into the plastic facia.
If you have threaded inserts then my guess would be a 8mm metric machine screw.