I'll make all the Tracker Dan sheaths you want at $100 a pop. They're not difficult or time consuming to make and you certainly don't need several iterations to get it right.
Standard ambi sheath only works for certain blade designs. Retention is the issue. TD / Watson blades, set retention on the quillion bump. AMTAC catches a ridge on the handle. RAT catches a notch in the handle. Blackie Collins catches a divot in the handle. Dynamis is friction fit. Everything else using a TD style sheath is based on some variant of those listed. This is why most makers either won't offer them or only offer them for certain blades.
Surf / Deep sheath is more flexible in fitment as it's friction fit against the handle rather than a true retention sheath. It works best with thinner slab handles or wrapped handles. You can make it work with just about any handle but the trade off is bulkiness.