Again, thank you for all of your input, suggestions, photos, etc.
I went with the Kriega US20, and it was in stock at the local Cycle Gear store. A bit larger than I was looking for, but plenty or space for tools, gloves and my old Belstaff jacket. It comes with various straps that facilitate installation on different bikes--a major plus!
I am riding tomorrow (Sunday) with a small group; the Norton tank and side covers are still at the paint shop, so the bag is strapped on to the Vincent seat. The bag should easily tie to the Norton frame using the provided straps.
Regards,
Russ
998cc