Yes John, that was what threw me - that configuration of round spike base and squared off front visor is (as I understand it) unique to just two units in Wurttemburg : Border Guards (neusilber mounts) and the Feldgendarmes (gilt mounts). But I think that both used curved chinscales, so can't explain why this one has flat scales - unless I am just plain wrong! (Perfectly likely!)
Hope someone can enlighten us and, of course, Amy too!
Best,
Steve
Edit: I just found the reference to the two unique units using this configuration in a post of Tony's back in 2017.
Model 1891 Württemberg Steueraufseher und Grenz-wache Helmet
I was misquoting him: they were not Feldgendarmes but 'Landjager Korps'.