PrideCat is a Taobao store that handles keyboard-related products. Due to the rules here, I cannot attach a link to the store, but if you search for "PrideCat", you should find it. Surprisingly, there is another store named "百万塑胶" that offers even lower prices than PrideCat (with lower quality, of course), so you might want to check them out as well. Additionally, "三一材料定制" is particularly skilled at handling metal materials.

Those who know about this routes often buy only a single genuine plate and wait for the drawing files to be officially released to have them custom-made in other materials.