Yes I remember this stunning sword. You cleaned it so well.
The nearest mark I can find in Kinman’s book has a reference to the Wallace collection which looks about right, although it doesn’t show the mark nor mention ”Viennese.” It doesn’t give any name of the maker/smith but states Solingen which corresponds with the running wolf mark on your blade. Could the number 1518 be the Bible’s John 15:18?
https://www.kingjamesbibleonline.org/John-15-18/