Vintage scene - dildo salesgirl - pic unrelated

Original scene was probably from 70s early 80s, there is a guy and a girl on a couch. The guy was the typical 70s moustached man, the girl was a brunette I believe. They were going at it hot and heavy when someone comes to the door. The man gets up and opens the door and let's in a blonde dildo salesgirl. She is shy and timid and so he gets back down to business. The salesgirl sits next to the couch and a chair and watches and eventually they'll join in together.

Not much to go on but every great if somebody knew this scene and I can find the original. I've looked all over sites and because it's so General without actors names or a title I can't find it.
Pic is unrelated as I couldn't find anything on this one.