Reasonably likely IF you've already got a JAA IR(H) on a twin i.e. you get an IR(H) an twin squirrel rating (c. £40k in total). A type rating on whichever helicopter your prospective employer uses is therefore likely although you may well be bonded.
Unlike fixed wing, heli type ratings are not the big deal; it's the IR that is.
Cheers
Whirls