I was only looking at an article this morning, dated June 1964. In addition to Perris and Ahearn, they were ridden by Bert Schneider and Hugh Anderson, though I don't think Hugh rode them very often.
They were christened "whispering death", by Ahearn.
I would imagine that Suzuki have one or two tucked away in their museum.
I would have thought that they were miniature RG500s.