Agree, I think I've seen it as an option too, but I don't recall seeing an actual car.

Could you post a photo of your car?

Definitely, the 1968-1970 Road Runners, there were full-vinyl-roof cars (you can see them doing an internet Image search,) but 1971-1974, I'm not seeing any yet.

Doesn't mean yours isn't real, it could well be.

Have you looked underneath seats, etc, for a Build-Sheet? My '71 Charger still had its Build-Sheet under the rear seat, but I pulled it and misplaced it sometime during the 1980's or early 1990's.

Since I'm a pack-rat (to some degree) I probably kept it, but not sure where... I should have returned it to the car.