Gunter:
Below is what I remember to be an E. Schmidt & Habermann/Oscar Merkel & Co on the floorplate with similar stamps along with MERCO. It has the Kelber script L as well as the interlaced J&Y. I had referred to this pair as a double duck stamp as if you view it from the side it does somewhat resemble a duck head. Anyway, let me search for additional images as well as a maker with a 366xxx range serial number.



http://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=183924&page=all

Kind Regards,

Raimey
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