Well, you can always cut it from the copper pipe, and make the symbols with chemicals for etching electronic boards - from my experience sodium persulfate is easy to use, cheap and quite safe if you of course use some basic safety precausions. You can secure the fields that you want to be not etched with permanent marker and paint the symbols with fineliner marker - they will be not etched.
I have once described the process on forum: Showing Art - #55 by Seraph