Ivan,
This sounds like a HI blade from the period when HI was first trying to get its smiths to mark their knives.
Only one could write, so for a while all the blades were marked KGR. They knew those crazy westerners wanted initials on the knives, but did not understand that they were interested in the man that created the knife.
It's straightened out now, and the HI smiths are putting unique symbols on the knives. The knife you have is an interesting point in the evolution of the khukuri, marking a transition where the individual smith began to be acknowledged for his artistry.