My 1973 Dart with 318 has the quiet car package. Originally from the factory it had a resonator. I think the resonator and the tailpipe were one piece. Is that resonator available anyplace? I see a lot of them for earlier cars but not what I need. I think the outlet from the muffler is 1 7/8" diameter. I am not sure if the original muffler had the same diameter outlet. When the original one rusted out it was not replaced. I would like to restore that. The picture on top (figure 4) shows what I need.