WAN TO BUY: A quantity of 6-48 Case Colored Fillister Head Screws like Redfield used to supply with their early scope mounts and rings. Not picky about length, what have you got?
If you can't find anything - order a dozen or so from an industrial tool&parts supplier and experiment heating them with a torch and quick-quenching in oil - you can achieve a case-colored look this way OR option #2, get someone like CRAFTGUARD to nitre-blue some for you OR option#3, there was a guy on GB awhile back who did a lot of case hardening of components like floorplates, triggerguard, etc. that may be able to help you if you can find him.
Mike 6MM250, just did a Leupold mount and rings for me. Caseharden colors really jump out. I could not be more pleased.
Steve