I don't blame you for looking for those MD, they are by far my favorite. They fit me like a glove.
They came in plastic and wood. They also came in three sizes, S M & L.
The earliest wood ones had the name Fitz routed into the bottom of the grip. I've had custom made grips done from numerous folks and by far, Fitz grips fit me the best right out of the box.
They show up on e-bay and in those boxes of various stuff under the tables at gun shows.
The grips on the K-22 are the plastic ones. The bottom pair are wood. I was told that the wood is called "fruit wood".
Not much grain to it, but hard as wood can be. I wish I had an extra set to sell you.