1957er Kampfabzeichen der Kleinkampfmittel
The special war badge for personnel of these units was instituted on 30 November 1944.
The 1st to 4th grade were circular cloth badges; the 5th to 7th grade were pinback clasps. The 5th grade (bronze) was awarded after the fourth mission, the 6th grade (silver) after the seventh mission and the 7th and highest grade (gold) after the 10th mission.
It is not known whether the three highest grades were actually presented during the war, which is unsurprising, given the highly dangerous and often near-suicidal nature of this kind of warfare and the resultant high losses suffered by the men who waged it.
An argument could be made that these not actually 1957er awards: The original wartime design of these badges did not include a Swastika and thus remained unchanged for the post-war ones, which is why they were not included in the official designs for the 1957er awards of 1 February 1958. The clasps were, however, included in the official manufacturing regulations of 28 February 1958 (so I decided to use the term anyway).
Here they are now. The clasps are early versions with solid hingeblocks: