87 fleetwood brougham a/c question

[earlfleetwood]

I am still blowing cool and the compressor is still coming on, but its not cold. I went to the car wash today and cleaned the engine, and I noticed bubbling water up by the firewall on one of the a/c parts. Its where the line goes into the firewall and there is that large cylindrical part. A) is that normal B) can you still get a R12 system fixed and charged, and if not, will my 87 accept the 134a?