Thanks. I was a bit baffled when considering this solution, because "a certain site" reckons the car had a works-style body by Orpin, and the photo clearly shows a very individual design. Who am I to argue?
Thank you also for allowing me 3 stabs during the lock!
(Your latest puzzle posting confirms you've had a busy summer. I was wondering what was going on, because you don't usually have time to respond so quickly. I still haven't worked out where you saw this image - according to my geography it's in the Bay of Biscay! Presumably in the South-West.)