Bonjour Patrice,
This is only my opinion, but this mark identifies BING as the manufacturer...
and they were one of the two authorized original manufacturers of the Trommelmagazine...
The photographs are of good focus, and the mark appears genuine, but there is no way to tell if the item has been recently fabricated, stamped and artificially aged to appear genuine...
Even obvious reproduction loading tools cost several hundred dollars when you find them...
This current price appears to be close to the value if this item is genuine or maybe a little high. If you win it, make sure you get the opportunity to return the merchandise if after receiving the tool, it appears to have been faked...
Good luck on the auction.