In the late 1920s M. Etienne Bourgey of Paris was fortunate enough to purchase the owner's share of the Arras treasure. This included six of the nine large gold medallions. M. Bourgey made high quality electrotypes of his medallions and was also given sole rights to copy the three medallions retained by the city of Arras. The electrotypes, in gilt copper, were of the finest quality and were produced for institutions and collectors. They were produced in a limited edition and were all numbered on the edge. The British Museum possesses a set and they are frequently displayed.
In January 1928, the two page advertisement shown above appeared in Spink's Numismatic Circular. Sets of these electrotypes were available for £10 each including case or one could buy a copy of the Arras medallion on its own for the princely sum of £3. The smaller medallions could be had for a £1 a piece.
These electrotypes rarely come on to the open market, either singly or in sets, and are keenly competed for when they do.
PS And yes, I did check with Spink and they are all sold out!