It took 2 hours for my answer, thanks hero! I guess I can give up hope of finding cleats for these things. Too bad, they're great.Weird thing is that I was just looking through some old Bicycle Guide magazines, and then saw your post. They're the Avant Sport Talon Pedal Binding System. Were available from West Coast Cycles for about $100. Made of "Verton" and were flexible to provide float. Screw tension adjusted by the allen screw. Weighs 134 grams.
Bicycle Guide, May 1989, page 94.