I too saw an early John Holmes that I'm going to try to find.
I'll look out for your's too.
The one I remember seeing was a slim woman at a table and I think John comes in to eat or drink and she moves round the table and stands in front of him. He sits and fondles her before they both are up on their feet in front of the table and undress.
John has a massive big dick (not fully erect - but very impressive) swinging about between his and her legs, deliberately trapping it and letting it swing so the camera gets a good look before she goes down on him.
The scene is shot in a studio.
I'll look for it later or tomorrow...... maybe if anyone has any clues to title or her name. that would help...?