You should google it. I know the topic of porn performers who can sing has come up before. Years ago, somebody released an album of porn performers singing. I used to see it at Rhino Records when it was on Westwood Boulevard in Los Angeles. Never picked up a copy and this has to be at least 30 years ago. I believe Marilyn Chambers played a country western singer in an adult movie and I heard she did a pretty good job. Not sure if the soundtrack ever came out though. Perhaps there is a dvd or vhs of the movie floating around, but I don't recall the title. You might be able to figure it out if you check her iafd listing. Since I never purchased any of these items I'm not much help, but perhaps this will jog somebody's memory.
I did buy Freddie Blassie's (he was a wrestler) "Pencil Neck Geek" (his catchphrase) in blood red vinyl. Also Jane Bond and the Undercover Men's LP which had a song sung from the perspective of an inflatable sex doll. Yeah, I've got plenty of oddball stuff, but no recordings of porn performers.

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