Looks to be an original M.K. 1 variant produced in the Gablonz area.
The ball hinge hardware is typical for awards from this area.
This badge is part of a series of M.K. 1-7 marked ISA's with the M.K. 1 the most prevalent.
It is theorized that the initials "M.K." stands for Metall und Kunststoff but solid proof has yet to surface.
Here is a bronze grade M.K. 1 to compare.
Best regards, fischer
Nice MK1, as my mate says. Stewy
Thanks everyone. Rob/