A teaser, as it were, but something basically fell into my grubby little paws tonight.
I considered it one of my Mauser Holy Grails, so it's turning out to be a very good, albeit early, Christmas this year.
Q: When is a K98 Mauser not a K98 Mauser?
A: When it's a K. K. Wehrsportgewehr made by the Gustloff-Werke in Suhl.
The SAd.NASDP stock cartouche is very obvious, as are two examples of a type of Waffenampt eagle on the barrel and receiver, albeit with an "N" versus the typical swastika underneath.
Different views, starting with the receiver ring:
Right side receiver markings, showing the toggle safety:
Left side receiver markings, Waffenamts?
Muzzle end, bayo lug accepts standard 98 Mauser bayonet...
Happy dance of joy!