Yeah the sheath thing is limiting.....I am gonna go the Andy route and manufactor one of my own design.
Well, if you want to make one like mine, I'll put the link below to my how-to if you want to reference it. I'm working on a new size one for a M6/Scrapper 6. I'll post pics of it on Rat Chat when I'm done.
The new & improved $2 camo duct tape/cardboard RM sheath with step-by-step pics