I didn't think they were that early. The example you show looks more like mid 80's than 70's. Of course, you know what stone, etc. the collateral equipment was...I don't. I also don't think the numbers were quite large, as proof in fact by the small amount of them out there.
We haven't heard from "Crutch" on this. I "KNOW" how much he loves the sixteen special fighter!!
Best, Capt. Chris