Hi! I bought this Shin Gunto Officer Japanese Sword in an auction a few years ago. And I was looking into selling it now. I was doing some research and I see a serial number 40127 which lets me know it's mass produced. But the fitting is quite unusual and I don't see others with such ornate fittings. Can someone tell me if this might be original? It has oxidated quite a lot (made of some sort of metal). Any help would be appreciated.