AC questions for the experts

My 93 was maybe the last R-12 system year but the R134 conversion was a screw on valve, sticker and a bottle of PAG. It Worked. Last time I bought some R12 from someone legit, I just had to sign a waiver saying I would not resell it. R1234xyz is the new Euro stuff and its friggin liquid gold, or so they seem to price it as.