Hi Fernando,
These seem to be reasonably rare, and the term 'sangin' seems correct from the sources I can find. These were used apparantly on matchlocks, I believe the toradar. The references I have found all suggest 18th century, and the form generally corresponds to yours with the double extensions, which are lashed to the barrel of the gun.
The type was known in Mysore with Tipu Sultans guards (Elgood, p.165) but the style is more elaborate, and indeed with 'animal imaging' present, as was often the case with his forces' weapons and uniforms.
Egerton lists a 'sangin' from Nepal (#353), and Wallis & Wallis sold one in 2003 which apparantly had a red & white horsehair plume attached. It would be interesting to discover what pageantry or ceremonial significance this had.
Incredibly nice piece Fernando, and thank you for always sharing these 'conquests'
here!!!
All the best,
Jim