They won't repair or replace them anymore to my knowledge. During the warranty period they would send you a replacement one for free most of the time. Now that the warranty has passed, I don't know that there is much you can do.
As much as I hate to say it, best advice is to put it on the shelf as a collectable and get a standard edition to replace it.
There are a handful of services that will repair them (basically change all the internals and reuse the case), but in most cases this costs as much as getting a brand new controller and would be without warranty in the event of failure.
