Hi All!

I wanted to see if anyone out there had an idea of when the gloss black, copper plated hardware Slingerland drums were made. There is a set on eBay, has been for quite awhile, that looks pretty sharp. This is the only one I've ever seen

https://www.ebay.com/itm/122891637938?ul_noapp=true

This is not to be confused with the Black Gold sets of the early to mid 80s. In fact the post suggests these are late 70s and are 5 ply, Niles badges. It appears to be the Super Rock kit #51N based on the sizes. How long was the 51N available? How rare are these drums? I searched the forum, one thread suggested only a hundred or so of these were ever made? Could this be? Just wondered if anyone has any info or input on these.

Thanks!!