There are several books on the subject such as 'Ocean Bridge' by Carl Christie, 'Ferryman' by Air Commodore 'Taffy' Powell and 'Ferry Command' by Don McVicar, as well as 'Atlantic Bridge', a wartime booklet that regularly comes up on ebay. However, none really have any photos at all of uniform. I have another, very large book produced during the war (thin but large format) of which Ive only ever seen two copies but is filled with photos. I believe all records of Ferry Command were destroyed after the war so finding information is hard.
Ferry Command was exclusively manned with civilians at the start, although the 'top brass' were service personnel. Later crews from all the Empire services were seconded (as well as a few odd from Norway etc), who wore their standard uniform. By that time they were generally Transport Command, 45 Group R.A.F. The civilians continued to wear their own uniform.