Hello Charles,
Thanks for posting another enigma!
This time I'm more inclined to play devil's advocate and believe we should seriously consider sales to those who travel for pleasure, I'm afraid.
Most piso halasan were first and foremost for status/ceremonial wear.
Ignoring the double feature, the scabbard resembles the standard
Karo kalasan scabbard a bit; however it is not of traditional style/decoration, especially for a status piece!
A silver ferrule is again a
Karo feature while these are
Toba hilts which may have casted brass ferrules (more of a selut than a ferrule for the usual stag hilts though).
The blades should exhibit a hardened edge (or laminated construction) upon etching which is tough to ascertain from the pics. These
Karo blades got (and get?) forged well into recent times.
Patina is not a reliable indicator for Batak since early tourist pieces are now way older than 100 years: as mentioned recently, there were non-traditional workshops for the curio market already in the late 19th century...
Regards,
Kai