Yeah the suspension, as good as it is, is nothing flash; just normal strut, shock insert and coil spring on the collar. If they wont license it with the coil overs then you will indeed need the factory struts, inserts and springs. Providing the mounts have not been modified to suit the coil overs?
The next question is whether you have an pre 85 or 85-89 AW11 as the suspension is not interchangeable.
Finally do you want to keep the coil overs or are you interested in a trade? I may know someone who is interested if that is the case.