I reckon they're Scotts as well.
I had a pair and I was a poor boy in those days (come to think of it, I still am)! I absolutely hated the bloody things and only rode one race meeting with them and chucked them in the garage cupboard. In the early 90s I found them again and wore them at a Nepean dirt track. Unfortunately the same issues I hated for them fifteen years earlier were still there. Call me crazy but I like to feel my gear changes. With the Scotts (Heckels as well) there was next to no feel through the boot so missed gear changes were par for the course. It wasn't so bad with the Maico but I raced a CZ as well and I couldn't get those gear changes right with the Scotts. A switch back to my old Ashman Red Devils and the gear changes were right again.
I sold the Scotts about five years ago for $50 only to find that I could have got a couple of hundred for 'em on eBay.
Scott has just released a new version of the plastic boot, the Scott Genius. You'd think they'd have learned not to bother after the market failure of thirty years ago. The latest ADB reports that gear changing is still awkward. At $799 a pair I don't think too many will make the mistake we made 30 years ago.