Hello.. Iserlohn is a town in Germany. Look above the plate, two blind rivets? From an earlier, removed plate? Do you have a renamed reel, the owners plate is there, but not the makers. Open the reel and check those two blind ones from the inside, do they have a certain purpose? Yours borano20
There was a German guy by the name of Hans Wurm who was ( I think still is) making Bogdan copies or clones. I think his reels were labeled either with his name or Gentle Craft. Not sure what the name means or where it comes from. That was the only German that I know of that was making any Bogdan copies. There is a guy on the Classic Fly Rod Forum who is very knowledgeable about Bogdans (as well as copies) and could maybe give you some more info. You can PM me and I can provide you with his contact.
Have a look on flyreelmania it has a list of all reels and kept pretty much up to date. The Serpentine section has all S handles.
The Swedish McSteen seems to be the closest to that reel, though there are a few differences.
There are also a few Chinese copies floating about (Jaz&John), there was a post here about one of these reels.