That's frustrating at such a low mileage... makes me glad I bought the extended warranty on the wife's G on Friday! Have you been towing things with your FX?
In any case, I would contact Infiniti of Scottsdale's parts department.
http://www.everythinginfiniti.com
They can tell you if the bushing is available separately. They might also be able to get you a discount on the part... although there may be a non-compete agreement with the service department if you're in the Scottsdale area.
Welcome to NICO!
Heath