Jim M,

Your observations about the earliest known date identifying these Huhnlein High Leader daggers beig in 1974 (Angolia book) is most pertinent.

I went back to the earlier thread on this subject (NSKK High Leader dagger, started by Craig Gottlieb, August 2007), and noted the following submission by Ron Weinand:
Posted 03 August 2007 09:39
The High Leader NSKK Dagger with damascus blade has been known to be in collections as long as I have been in this hobby (50 years).