Hi Luke,
After inspection, it looks as though the AC compressor had overheated internally and seized.
The A/C specialist suspected the pressure's were too high due to the older original condensor design as the system was not designed to operate on R134a.
We used PAG46 oil in the new A/C compressor. Between 160-180ml.
Yes they replaced the reciever drier, cleaned out all the lines, even replaced one. Also did the evaporator, TX valve under the dash. Cleaned the lined out with Shellite. The works.