Where can you buy R-12 freon?
you can't. the government banned R-12 freon in the 1990's. i wish i could get some, it gets much colder than r-134.
anything 94 and below is going to be r12, unless someone has put a retrofit kit on there then it could be r134a. some people have been know to put other dangerous things in there freon. r12 freon is really expensive. the best thing to do is go to local auto parts store and buy a r12 to r134a retrofit kit and have the system retrofitted