Valentin:
Thanks for the effort and it is possible if you tap out the crosspin holding the forend providing full view of the marks, we might could solve the puzzle. Note the cut-out in the doll's head extension which mates with the Westley Richard's crossbolt, or bolting mechanism(not the same as the Greener Crossbolt). Also either the "Crown" over "GR" is a control stamp or notes that Gastinne-Renette Arq. made the tubes/knitted the tubeset. From the snippet view we have, you are correct and in 1923 there was some proof effort in Austria.

The Arq. is arquebusier, thanks to Mr. Brown and other French firearms merchants were sourced by courts: http://www.doublegunshop.com/forums/ubbt...true#Post253663

The French firearms merchants sourced components or sporting weapons from their British counterparts.

Kind Regards,

Raimey
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