no luck finding anyone selling copper bezel wire, or copper bezel cups or even on how to make a bezel out of copper sheet.
Barbe, you can cut your own bezel wire/strip out of thin copper
sheet (28 and 30 gauge sheet are available at Indian Jewelers
Supply), and make bezel bases out of thicker copper sheet. I don’t
know of anyone who makes copper bezel cups, but IJS does make their
own brass and nickel-silver bezel cups. If you’re just experimenting,
perhaps the color contrast would be interesting. Since there is yet
no solder that ends up being copper in color (despite what some ads
say), there will be a color contrast from that process, as well.