Alex, the term 'calyx' refers to the flueret like element on the back of the blade which appears in line with the backstrap of the hilt. As mentioned, this has consistantly appeared to me a Central Asian affectation.
As has been noted, from the mid 19th century, the demarcation between North India and Central Asia, that is Afghanistan and the Northwest Frontier regions that are now Pakistan were anything but clear. Naturally the cross diffusion of weapons was typical, and if I am not mistaken, the Afghan daggers similar to the pesh kabz were either karud or the choora, both with straight rather than recurved blade. We know that tulwars were often found in Afghan regions, and the paluoar, the distinctively recognized Afghan sabre likely had its origins in the Deccan.
Tim, incredibly astute association there!!!
Those figures do indeed seem to be Kalash, and the Kalash do remain as an independant tribe in Chitral. They still maintain distinct tribal customs and traditions from thier origins in Kafiristan and I once had very interesting communications with a group here in the U.S. who are organized to preserve thier tribal identity. The Kafirs were the focus of the Rudyard Kipling classic "The Man Who Would be King".
All best regards,
Jim