Thanks. I remember vaguely the original was for some South American government official but didn't recall it was Mexico. II imagine Winchester was hoping for a big military contract.) Nor do I recall seeing a price, but $28k is rather impressive. At the time, I did look up the properties of various silver alloys and found several with suitable tensile strength, which surprised me since silver isn't very strong. Also, the weight of the silver in the frame was only a few hundred dollars at that time, which also surprised me.
My thoughts were that a decent aluminum alloy would today make for a nice '66, especially when combined with the more slender barrel tapers Miroku uses on their '66 and '73 pattern rifles. While it's strong enough, there is the question would it be stiff enough in such a long frame. Boing