It is my understanding that in the 'old days' a kukri that had been 'blooded' in combat would either stay in the family or be passed on to the next military man in the family. While this sounds good and works in theory there were specific issue knives that were required. And then there was the distinction between a parade/inspection knife vs a working model. Bottom line is yes, they were sold or traded.
There are model numbers and there are knives stamped with a soldier's individual ID number. Some of these go back to the late 1890s, but it depended on the regiment. I have had knives that could be traced to the owner.
The newer issue kukris from 1950 on become available quite readily so apparently they do get out of Nepal. Many of the tourist pieces are stamped with various army markings to give the air of authenticity and anything can come and go with the right application of currency. A lot of the issue knives never made it back to Nepal. Hong Kong, Brunei, Malaysia and of course England are probably good sources from the old to the new. France also had a fair share of kukris left after WW I and I would consider India the biggest resource for both excellent and incredibly crappy examples.
