The note to this song when it appeared on Topic Record 'Second Shift' (1958) was as follows.
"Charlie Mayo, locomotive fireman of Kings Cross loco depot, wrote the words to this hard-hitting song immediately after the colour bar strike of the Kings Cross railwaymen in 1957. The air is by Ewan MacColl."
Judging by how Ewan made tunes, I would guess that he based this one on'Searching For Young Lambs".
Billy - Thanks for letting us know that Charlie is still going strong and a link to where we can get his book.
Jim Carroll