Tom, you could sew a few strips of 1" nylon webbing across the front (spaced 1" apart) and stiched "vertically up the sheath" to make a hybrid leather/MOLLE capable sheath. Seemingly everything made today has MOLLE/PALS on it and nearly all pouches are now MOLLE/PALS compatible.

JYD #123 The great one formerly known as Architect.

I am now a fictional British television police officer (currently a Detective Sgt) at Thames Valley Station. My governor is Detective Inspector Fred Thursday and it’s 1969.