I personally have not done this type of work, but in a previous job came across guys who did and it's not all it's cracked up to be, very little flying, (one guy said he'd managed 14hrs in a year!
and you'll normally be asked to do some other role on the boat, but that I guess depends on the operator.
Luvair(I think thats how you spell it) do this sort of thing but you'll need a shed load of hours.
Good Luck with the tan!