Since you use Marilyn Chambers to start this thread, don't forget that she was a former "Ivory Soap" box model and if you pay attention, in most of her movies you would find this very box someplace in a scene.
other images of her in various stages of life including what appears to be another cover shot but I don't know if that was from after she got fired from Ivory or before.
As an aspiring actress, she had a small role in the movie "The Owl and the Pussycat" but once she did porn, mainstream movies never really used her again.
But another porn star would have to be Traci Lords. She was extremely controversial because she had lied about her age when starting her porn career and so anyone who owned any of her videos before she turned 18 was in possession of child porn and once that became known, it didn't matter how you bought it, you had to destroy it of face felony charges if caught with it.
But Traci moved to mainstream acting with limited success. She had a recurring role on an NBC show in the late 90's called "The Profiler" as the ongoing serial killer Jack's protege "Jill". The show did a very good job of turning her into a very suitable look alike for the main character, Ally Walker, using makeup and hair.