Update:
The copper arrived today (2 weeks, not bad), while the ad said it would ship from Hong Kong, the return address on the label was New York...that's interesting?
The material is just what the Doctor ordered...umm, I mean what the boolit caster ordered, LOL.
It's a nice looking 4" wide roll, 40" long, shiny copper, Not bad for $8 plus $2 shipping. It cuts into strips easy, and cuts/forms in my FCIII dies nicely. I crimped a few onto some freshly cast 225438 boolits, from a vintage mold that is also new to me. The .008 checks crimped on nicely.
If you search Fleabay for "99.9% Pure Copper Cu Metal Sheet Foil Plate Strip 0.2mm x 100mm x 1000mm" you will likely see the ad of the product I ordered.