Crikey, my senility is worse than I'd imagined. I thought that the short straight from Sear to the bend onto the Norwich Straight was called Revett, but I've just checked and it wasn't named that until 1974. And Russell didn't get built until 1965. I suppose that's because my regular visits began about then, cycling 18 miles from Norwich on my Haddon tourer, with Sturmey-Archer 3-speed and dynamo hub.
I had always assumed that Russell was always there, or at least had been for some time. You're all correct about the Bombhole - I've read a history of Snetterton Heath airfield, and no bombs exploded there intentional or otherwise.
The proximity of the Norwich Straight to the main road was a cause of great joy to me as a child, since it was not uncommon to see a Lotus being tested there off-season, and because of the time of year there were few leaves on the trees and bushes, and a good view could be had. All gone now, although I understand that modern-day competitors rather like the new circuit.