Converting to R-134a

I have a 1974 dodge dart and the a/c compressor is stuck. The car originally had r-12 freon I would like to change the compressor and convert to r-134a. My question is do i need to change the accumulator and drier as well as all the o-rings and lines. Any helo woudl be appreciated. Also if I do need to change all this stuff any source for securing the parts woudl be helpful