I'm sure anything is possibe!

I swear i saw an airconditioner unit for an A-series on Ebay not that long ago, it had a picture of the unit that fits under the glovebox, not sure if it had the compressor and the complete kit though, i only had a quick look.

My mate bought a Hilux with a unit similar to the pic the sidedraught posted, he found out later on that that particular unit is an aftermarket set-up, and to buy a new complete set-up cost a fair bit, it was already in the car when he purchased it. It worked quite well! espeically if you were the passenger, it blew a cool breeze up your shorts!!
The only problem with it was because of where it's situated when we went shooting or up the bush on the 4WD tracks,i (being the passenger) used to always bash my knees and shins on the bloody thing! other than that it worked quite well