I have looked for exactly the same thing in 200 grains (like the old Knight Red Hots) a few years ago. I got lucky when Barnes finally came out with the 200 grain 45 cal 460 S&W bullet. They have another one in 275 grain for that cartridge; would that work for you? At one time SMI was able to get Barnes to run modest bulk quantities for them, but I think not anymore. They wouldn't do anything special for me either. I'm going from memory, but I think they want something like 5,000 pieces as a minimum bulk order. The only other source for an all-copper bullet that I know of is Magtech 225 grain, but it is only in loaded ammo.