Morris Minor Owners Club

That is very helpful, thanks.
The colour, which may not show up too well in the photo, was an olive green, so if Clarendon was a green that could be it.

The picture was taken sometime between 1962-65, at Whipsnade. I'd love to know if this car is still around, though I suspect it isn't. Would still be interesting to know the exact model minor this is and what the official description of the colour was. It had the indicator flags but these weren't op...