Thanks Kubur. What you say makes a lot of sense, but..some questions are still open.
-The blades on Corrado26's pieces are very different. They are definately of good quality, but the are not typical koummya style. Hollow forged style is seen in koummyas that I think are from about the turn of the 19th c., but the extra bevel is strange. Some are marked with B and a number. Therefore, mariusgmioc's question about their origin is good one.
-The similarity to the guns is not that obvious, except for the use of camel bone plates.
So, I agree that these are probably early pieces for the tourist market.
Also, quality and age are not 1:1. Probably, some koummyas were made in less professional workshops, but are basically the same age as what they imitate ("village type") and have even been used by locals.
It is still true that most 19th c. pieces are of higher (but variable) quality and were made in one of the traditional styles described in
http://nimcha.fr/koummya.htm