I had a response from Rolex today about my fathers Chronograph, not too much information but it is a relief to know they believe it is real. Now it's time to have it restored I guess, Rolex say the case is beyond repair but I believe there are ways
And I quote;
We thank you for your enquiry of 23 January 2012 about your vintage Chronograph.
As far as we can tell from your photographs, the watch is in original condition. However, we sincerely regret to inform you that a restoration is not possible. The watchcase is so heavily corroded that any attempt of repair is impossible. We dont have a replacement case available as this model has been discontinued many years ago. It was manufactured in the 1940s.
Service Mondial World Service
ROLEX SA - rue François-Dussaud, 3-5-7
1211 Genève 26 Suisse"