I generally use my khuks as camp knives, or they ride inside my pack. I have made leather replacement sheaths for some of mine, but usually just use what they come in.
One thing lots of folks do is remove the karda and chakma, and use a pair of pliers to pull the little leather retainers out of the sheath. They are usually just a rolled strip of leather stapled into the larger sheath.
Once they are out, you can slide the frog higher on the sheath. It will compress the top of the sheath. This makes the profile slimmer, and it lets the whole knife hang lower on your belt.
I've taken to giving the kardas away to people to use as letter openers.
Andy