I own a shop, and think this: There will be several that will work on your vehicle, but the "only" people who have the cross reference software are junkyards. This because no one else has use for it. They pay big bucks each year to obtain this information, and use it in order to know what parts they have, as well as what vehicles the parts they have will work on. I would call several junkyards in your area to see what the going price for the compressor is. I would also call a few parts stores to see what a rebuilt one would cost. Believe this or not, but I have saw some parts stores that had a better price on a rebuilt one than what the junkyard wanted for it. The unit on yours is more than likely an AC/Delco, and many other vehicles such as the Blazer, Yukon, or Buick compressor will be the same. Many times the name Cadillac raises the price for the same part that's on a cheaper built vehicle. An example would be with the Alternator. Many will work on the Cadillac, but they have a large price on one for yours, while many others that are much cheaper will work.
Glad to help out, Good Luck!!!