Yes there IS an inner seal. It is light grey in color. Fits around the outer edge.

The Holy Grail of Westy parts!

I searched every page of my Westfalia parts manual from 9/67 up but I cannot find it listed.

I have one and one only on the sliding door jalousie of my 77 Westy. It came from an earlier year Westy. I have only seen them on early, i.e. 68-72, Westies.

I can take pics of it if any one wants to see what it looks like.