Thanks. Still wondering if names of buyers were ever engraved on lockplates as a method of identification.
Searched Dewson and found a construction company by that name and thats it. Emailed them and got no return.
In contact with Theodore Roosevelt National Park trying to get name of cook at Elkhorn Ranch. I suspect he sold the gun in Dawson ND on his way back east after the cattle operation folded.

So looks like the only hope now is British newspapers or business listings.
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