The Kriegsabzeichen für Minensuch is indeed a nice Deumer in zinc.
Deumer was the only recognised maker to use a horizontal pin configuration for these badges which makes them easy to identify. If they don't look like the above or below then it is likely to be a fake.
Deumer also made these badges with a vertical pin set up too.
Looking for LDO marked EK2s and items relating to U-406.....