Factory French, or Markneukirchen Bow?

auction

Wondering if this bow is a factory french, or a German mark... copy for a Vuillaume.  Certainly the JB style, and I know the Germans
made these copies, but how can I tell where it was made?  Seem to remember Martin saying something about the metal plate being pinned, or screwed depending on........?  Quality is noticably low on the frog eyes.

ARod

Looks like it may be right the stamp looks ok, the lapping looks right for the Vuillaume shop. Wood doesnt look great quality,but it may just be the photo.. Get it seen by someone. Voirin made most of these ,but also Simon and Charles Peccatte.