You would more than likely have to change out the entire engine compartment wiring harness and PCM along with adding all the other AC system components
I would guess around a $1000 or so. Just depends on if you have to replace the harness and what it cost. The best thing to do is go to a junk yard and pull all the brackets off of another car. This will save you some money.
your going to be looking at alot more than a grand. The AC compressor for that car is almost $500 by its self. then add another $3-350 for the condenser and fan assembly. and thats just getting started. Youll have over 2 grand in it