H.S. Newcombe who wrote books & articles on 35mm Photography etc was also the owner of a large camera store. He wrote a very interesting article in the 1950 BJP Almanac "A Photographic Dealer takes stock" he complained about the dearth of new cameras from the Continent and that all dealers had to sell was second hand stock apart from some newer models from British manufacturers, but at that point there were no precision British 35mm cameras to rival Leica, Contax, Exacta etc, just 120 and 620 folding cameras and the odd 120 SLR.
Where Britain excelled in 1950 was making new lenses to fit German cameras, Dallmeyer, Wray, Taylor Hobson, Ross etc all amde lenses which could give a new lease of life to pre-WWII and captured German cameras. Newcombe lists all these in his book on 35mm Technique.
With government help many German cameras were copied the pinnacle being the Reid III - a Leica copy that was better made than the camera it was based on with a better standard lens, other companies copied different cameras, MPP the first Linhof Technika (MicroTechnical) and the Rolleicord (Microcord) & Rolleiflex (Microflex), AGI the Reflex Korelle (Agiflex).
The 50's saw a wide array of new 35mm cameras with interchangeable lens from a number of manufacturers, like the Ilford Witness few remained in production for very long, again Newcombe lists many in his books..
Ian