All of above... concur.

New photos = additional clues. Type 2 stamp on blade, possibly 1957 (?) to sometime in 1965 (type 1 continued into early '66). Choll=? not really qualified to address ... looks like an unusually right-angle type which was apparently short-lived very early '60s, but that opinion is base completely secondary scholorship. Bo could help answer. White print on stone, if original, would bring '62-'63 or so into play. Stone-swapping is an issue even more than sheath-swapping.

My guess now would be about 1962 HLK with west facing Randall-made sheath stamp. HOWEVER ... we should keep in mind that during this time period the Model 1 sheaths had the longest overlap of supply from Heiser than any other model.

Brown button HLK model 1 sheaths were still being shipped when most other models were being sheathed and shipped in baby dots. This is pretty well documented.