Thanks TB, again...
and Andrew for the links - look perfect
I have some extra dual 110V starters I bought for the Tron machine (FS2?) which I think are labelled the same as the one that is in the Defender so will check that and order and fit a 110V 50Hz ballast as advised.
These guys also seem to have one, middle of the page, for a good price.
http://vendparts.co.uk/acatalog/Balasts.html
Will update how I get on
Thanks again, especially advising on your Sundays!!
Alex