Someone posted the idea of minting copper bullion coins and/or bars for sale on EBAY. This seems like a good idea if the production costs are kept simple.
I used to work in the Metal Stamping industry. You would have to have dies made. Blank dies would be the cheaper route. You could add your own stamp later. I'd start with 1 ounce rounds and 1 pound bars. This could be done from the same material thickness and would be econimcal and make stacking very easy. Dies made with a logo or date would cost big $$ but would enhance the selling potential. As long as copper prices stay high, this may be profitable.
I still think the best way to invest in high grade copper is buying U.S. pre-82 cents but your bullion idea has merit. If you decide to do this, please send me a check for 2% of the profits. Thanks