You might find an answer if you put the question on timetrialing forum, there's a lot of older riders lurking there http://www.timetriallingforum.co.uk/
Thanks for that, I've now got the answers I was seeking - Silchester CC was a London club originating from North Kensington, formed in the 1930s and nothing to do with the village of that name near Basingstoke. It folded around 1966 And the clubs colours were orange and black...
You might find an answer if you put the question on timetrialing forum, there's a lot of older riders lurking there http://www.timetriallingforum.co.uk/