There is a picture of a pebbled DJ belt buckle on page 263 in Angola's book "Belt Buckles & Brocades and the Third Reich". If you have that book then try looking up the page.
as far as I remember I have not ever seen shown or mentioned a pebbled DJ buckle
in a regulation or catalogue. In my opinion fantasy.
The one in Angolia is also a put-together buckle. An old box was taken, the sigrune
poorly added. I once inspected the buckle at the house of the owner in Belgium!
Here is another one. For sale on a dealer's web site. Similar to the OP and the example in Angolia's book. This one is maker marked to OLC like Gillain's piece. Again appears to be a home crafted rune applied to a pebbled box.