They have not been bound, there are 104 separate magazines dating from Oct. 1939-----November 1946, published by Amalgamated Press Ltd Farrington St. London.
They are by Maj.-Gen. Sir Charles Gwynn [Editor, Daily Telegraph] and Sir John Hammerton.
This complete set of illustrated World War II history magazines unbound but complete in 104 parts in original wrappers edited by Sir John Hammerton and Major Gen. Sir Charles Gwynn were significant due to their timing as you mention from Oct. 1939-November 1946 and today do have moderate rare book value. They are found in libraries World wide from Australia, Canada, The UK, Washington to Texas..as well as other hard bound variations by Hammerton and Gwynn.
In fact, surveying International markets the fair market value today is 120.00-125.00 (USD) well preserved as you mention. These are not seen in great numbers on the market but are available if you were looking to sell, I would definitely try to get a bit more as a WWII enthusiast would certainly have interest in these and 200.00-250.00 (USD) is really an appropriate retail range for this set in this pristine shape. I hope this helps.
All my best, Dori