Corgi makes a nice O scale (1:50) PTC PCC. Nicholas Smith has one on their site. I have one that was motorized by PA Heritage Models.
But I don't know of any O scale PTC El or Subway cars.
You might be interested in Peter Lerro's print Shifting on Delaware Avenue.
I bought a copy of this print and it just dawned on me that I bought it very close to the vantage point of the artist. At an Atlantic Division meet on Delaware Avenue (now called Columbus Blvd.).