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 until yesterday!
$15 and I pay postage.
Doug