I have the plug
, top nut, and the barrel shaped housing for a late 1980's VDO Sumlog EL (as I remember...)
This is the black delrin plug
part that you put in when the paddle wheel
assembly is removed.
It is used, there are some light plier marks on the barrel housing, but it is still fully functional.
We got rid of the Sumlog years ago, but this stayed in the boat
$15 and I pay postage.