I will leave the place of manufacture up to the experts on the BCN site such as yourself.
All I know for certain is that the beads were sourced by me personally from Frank Beuhler's son after Frank passed away, along with many other strands of Native American beads Frank, his brother and Frank's family found at sites along the Columbia River over a 50 year period. Frank and his brother strung the strands when thet were over 75 years old.
The strand I have taken these pictures from is 8 feet long. Frank had a second strand of sky blues that was six feet long that I did not acquire with his collection.
I do believe that many of these sky blues were sourced through Native Americans trading with HBC fur traders. My wife's Uncle was an Indian trader from Waldport, Oregon in the late 1800s. He obtained many of his trade goods from the HBC post in Vancouver, Washington.