,005 copper will form really easy and You can cut it with scisors, but that would go pretty slow. I thought You were thinking of thicker material. The clay model will work fine, and then You can wax up the first cast and pour the other die against it. 2 plates with dowel pins to line them up and You have Your die set, just keep the plates parallell when You cast it, or You will need to go to a soft or spherical ram attachment to get uniform pressure.
Laser cut blanks would be the trick. Look at this website
http://www.drgnfly4g.com/ Randy is one of My blacksmithing friends, and has done some interesting things with laser cut material, and has the connections with someone who does short runs, if You need that service.