This is going to cause some controversy....
If my books are correct, the RAF carried the Big bombs in their inventory until the mid sixties.... They went thru a few modernizations over the years... The Brits didn't have an aircraft that could lift them up to the optimum Alt of 40k, until the Canberra/B57....
If you notice the old photo, of the single bomb in the building.... The scale seems off a little bit, as compared to your's.... Unless they used a midget in the old photo...
And the one I've seen, seemed much larger as well....
Hmmm, worthy of investigation...
I agree that the first photo, of the 2 bombs hanging, seems a little suspect...
OG