No need to take steering wheel off or touch the airbag!
I've just had to do this myself, on exactly the same car with exactly the same fault! The indicator/light stalk is a complete assembly that my dealer kept in stock & cost £50.
You need at torx screwdriver(star)-I think it was a 20 or 25- to undo the plastic housing around the steering column that the stalks pass through, (remove upper & lower) then undo the 2 screws that hold the unit on, unplug it & you're done. The hardest part is getting the plastic shroud around the steering column to clip back together!
I replaced it in less than 1/2 hour, on a Saturday morning as I was going on holiday.
Terry
June 2009