TK Custom will be a good outfit to work with. They charge for the alteration plus 10 TK moon clips for 45 ACP on a Ruger Redhawk. About $175.00 for just the alteration and 10 stainless steel moon clips. I believe a loader for the cartridges to the moon clips can be added. You should also include purchasing the tool for removing the spent cartridges without damaging the moon clips.