Set TC-L is a celluloid bowler identical to the figure from the original celluloid boxed set. Set TC-M is one 00 scale bowler figure without a base, that sits in the wicket stops.
Each TC-A fielding side also included a bowler in a fielding base, although this wasn’t a part of any of the boxed sets. This meant a slight change of rules in the caught and bowled rules between the two games.
Of the celluloid bowlers the white base is by far the most common. Green base bowlers do regularly appear in later Test Match sets, while the yellow bases crop up occasionally in earlier Test versions.
Like many, I’m sure, once my celluloid bowler eventually broke I used the 00 scale figure in its base. It worked really well I seem to remember, and its hard to understand why Subbuteo didn’t switch to a fully 00 scale bowler when they moved from card and celluloid in the 1960s.
Hence the white and black bowlers below right aren’t genuine Subbuteo pieces.
One genuine variation you can find is the set TC-L bowler holding a white ball. He hails from the Floodlighting Edition.