Considering your account of the path taken by the longarm, I do find it hard to believe considering the Belgian Powder test advertising in German on a Anson & Deeley Body Action platform destined to Canada. I would say it was a WWI trophy and brought back to Canada. Interesting too is that not only does it have a Greener Crossbolt & side clips, but an added lockup from the toplever?

There are initials in the well of the frame, but I cannot make them out from the fotos.

Serbus,

Raimey
rse