Changing the carrier for a change of ratio is, quite honestly, no big deal. They're not expensive and the carrier has to come out anyway to change the ratio. I wouldn't give it another thought.
But whether the installer will need a lower ratio version of the carrier depends on what your present ratio is and what ratio you require. Don't choose your next ratio based on whether you need a different carrier or not, base your ratio decision strictly on what size tires you wish to run, your transmission type, and which engine you have. If you find a new carrier is required so be it.