Hi Alex,
It is an Indian dagger all right. I don't discern any Japanese style/influence. Not even the small painted ball (which looks more Chinese to me).
I also got asimilar dagger but without such a history... and price tag. The red stones are rubies, the orange, agathes and the green... glass. For my knife, the ruby eyes are mounted in gold... while for the "shogunal gift" ... I'm not so sure...
