Actually, your turn signal switch being on the right is "factory correct" in the ultimate sense! They all originally came that way. Given the symetrical design of the column cover, etc. most of us moved it around to the left side of the column where we are all accustomed to it being on American cars. I am an original owner and that is what I did. For further confirmation, check out Section N (Electrical Equipment), page 31 of the Rootes Manual WSM.143. The pictorial of the dash area shows a left hand drive configeration with the turn signal switch on the right side of the column.
Regards, Gene