This type of knives seems to be found in the great area you have already mentioned. By your one I see some ornaments which look chinese.
I have a similar one:
http://www.vikingsword.com/vb/showth...ighlight=tibet
Your one look relative recent but made in traditional manner. I know that these knives sometimes are called lothi, see here:
http://www.oriental-arms.com/item.php?id=5657
Regards,
Detlef