I finally purchase an old book by Michael Roberts (1989) "People in Between", you don't see it in the shelves much these days. I came across a list drawn from the 1871 census in Colombo/coffee estates listing Nationalities, p 202. :
According to this list there was ONE Jew in Colombo/Coffee estates and she was FEMALE!!!!!!!!!!
There are other listings for nationality - Pole, Portuguese etc. Mmm, so we know there were others - they ended up in the cemetery! (to be blunt). Maybe they decided being Jewish, is not a nationality , which is true and they are correctly represented under other nationalities. Don't always believe what you see.