I am trying to find (I think it’s called) black anodized aluminum with a brushed finish. It needs to be at least 15” x 15”. My local supplier can’t get it and I don’t see sources online this size. I have attached a sample of what I want. Often old school music amps used this product. Anyone got leads?
There's a company called Aliexpress (?). There website has a lot of different sizes and thicknesses. Most of it decorative but it may serve your purpose. Good Luck!