Carol
I'm very interested in you theory of the 50's era....
With the whole collection, I do have photographs that I know were taken in the 50's, comparing this with a photograph of the 50's very different type of photographic paper, this is more like a card type, where the known 50's are more fine and slicker. Then comparing tonal rage, this photograph is very limited and much darker, where the photo's from the 50's have a larger grey scale tonal range.
Other indicators, I do know Vivary Park, and where the Lads are stood is near the War Memorial now stands, which has a large area of Tarmac surrounding it.. Vivary Park is in Taunton Somerset which was the headquarters for the Somerset Light Infantry.
Another problem, is that I know via likeness (the lad on the left is a splitting image of a nephew) that these are family members, but I don't have any male candidates that would fit the likely age, within the 50's era..