To add to Reg, I doubt the amount of morphine in the mixture was enough to be misuse-able. And I've definitely seen it on shelves in the past year or so, as well as the non-morphine kaolin mixture.
That's where you are wrong.
In the early days of my romance with Mrs Vernon, she got a dental abscess and was in excruciating pain that was not relieved by the pain killers prescribed by the dental hospital - they operated an emergency service back in the day. She had to wait two or three days for some antibiotics to act before treatment could commence and she was beside herself with the anticipation of a weekend of misery until....
I bought quite a few bottles of kaolin and morphine and using readily available household items and kitchen utensils I prepared a concentrated clay free elixir that could be rubbed into her gums. She spent the entire weekend off her box and when the dentist asked her, upon her return visit (I had to hold her up at times) to the dental hospital for treatment, "Where does it hurt?"
Her response was "Nowhere maannnn...."
I think that she decided I was her man for the rest of her life that weekend.