Among the more difficult to find pieces for my Track & Field Cocktail were the metal sheets which covered the speakers and vent holes. Presumably these covers prevent anyone from poking out the speakers or dropping their garbage inside the cabinet.
When I say difficult to find, what I really mean is I didn’t know what I was looking for. I had no idea of how to describe these sheets. Eventually, the phrase I stumbled onto that worked was perforated aluminum. I ended up ordering a 3’ x 3’ sheet from Amazon.com. Way more than I needed, but it could be useful down the road if I push forward with another project.