Very interesting! I have one of those plugs. I've always wondered if they are worth dragging around.
A couple of years ago, a neighbor came to my door with a very old metal tackle box and asked if I wanted it or he was going to throw it away.
I was kind enough to save him the trip to the dump!
It had reels and all sorts of plugs and spoons and spinners.
there was even a buisness card for the C-Q Cafe in Sekiu. It's so old the phone number is 3 digits.