A new A/C compressor will set you back ~$400, an A/C condenser something similar. Those and the hoses are the most common things to die. Make sure that they have not deleted the A/C on your car, either
ODO gear is a $25 part, and if you know what you are doing (Follow some of the online guides, or figure it out yourself as it's not that hard) you can install it yourself. Figure that a speedo shop will charge you $150 or so to pull the cluster and replace the gear.
Good luck in your search.