Highly unlikely this is still covered under the manufacturer warranty. If you have an extended warranty then possibly. Some compressors have a replaceable clutch, but when you look at part and labor cost to install a new clutch on an old compressor, it isn't worth it. If the old compressor was to fail you will have to replace the entire thing anyway, all to save a little money. Just have the entire compressor replaced.
No it is not, if your AC compressor has "frozen" up join the crowd...this is a common occurance for the XL-7. The recommendation from me is to avoid the repairs at the dealership and save yourself $1500 by going to a local auto mechanic and get the kit from Auto Zone or on-line... As an aside it tend to take out your steering belt with it at some point.