You could always make your own sheath. Find someone who has a heat gun you can borrow, find some foam and wood and clamps, and it'll cost you maybe $40 for a rivet flaring die and enough kydex and rivets and to make 3-4 sheaths.
It's actually pretty fun, too.
Or find a maker on here who can make one for you. Keep in mind that you might need to ship the knife to them.