I'd get the IR asap..
But you will be lucky to get a course in time. Try Tiger helicopters.
Like FlingWings said, if you get the IR now, you can then let it lapse and still have 7 years before you need to take the exams again. I'm not sure if it's 7 years from the issue of the IR or 7 years from when it lapses, but it's still a shed-load of time.
If N.Sea opportunities don't float your way now, you can sit on the re-validation until they do.
My 2 cents.