Yes you can still get R12 from an A/C shop here in CA, but expect to pay over $100/pnd and you will need at least 2lbs. 10yrs ago the price/lb was $80 when I converted my '90 to R134, so it may be more than $100/lb today. I had my low system evacuated and then filled it w/r134 oil and coolant. I was never that impressed w/the R134, it wouldn't drop the temps much below the high '80's and on 105+ days it was basically useless. My '90 is black so the straight conversion may work better in a lighter colored rig.
In early Spring 2005 after my A/C comp started making noise on start-up, I searched for an alternative product and came across product called Maxi-fridge a hydrocarbon(propane) based refrigerant. Here is a link
http://www.4x4wire.com/forums/showflat.php?Cat=&Board=UBB11&Number=892518&Forum=&Words=maxi-frig&Searchpage=0&Limit=25&Main=892518&Search=true&where=bodysub&Name=2560&daterange=1&newerval=&newertype=w&olderval=1&oldertype=w&bodyprev=#Post892518 to a post on 4x4wire about my testing of the two. It has been 3yrs now and I am still on the original 2 cans and the same comp, which hasn't made any noise since replacing the R134 w/the Maxi-frig, and the truck doesn't slow down when I hit the A/C button anymore either.
