I actually looked into this recently, but I unfortunately lost my momentum as I was writing a post about it and I didn't end up saving my research. I'm sure someone will be able to clean up whatever I get wrong.

There was a precursor to the Rockers that used B/O badges. The shell composition was different and badge placement on the bass was positioned on the batter side of the drum, like you can see in the picture. I don't know anything about the granitone (gray) interiors on these drums, but from what I remember they should be clear interiors.

You might ask if all the drums are gray and if any have a reinforcement ring. He could just be going off the one drum he bothered to look inside.

Edit: These might be early '80s Standards. The bass spurs have been updated and the shells have been re-wrapped, if so. It looks like these are mini classic lugs, which are what Standards had.

Of course, there might be a much simpler and much more obvious solution!

I'm not aware of Ludwig Rockers having blue/olive badges, but I'd say it's possible. There are plenty of Standard (sometimes referred to as Rocker) 5x14 chrome over wood snare drums with blue/olive badges.

The kit in the photo could be a Rocker because the kick has 8 lugs per side instead of 10.

Rockers would have the small classic lugs or standard lugs. Not sure if those are large or small classics.

I would assume that the kit has been re-wrapped unless told otherwise.

I'll ask about the reinforcement rings. Thanks for all your info! Bummer you lost momentum with your post, sounds like it would have been a valuable thing!

If it is an early 80s Standard, does that say anything about the quality/value versus the Rocker?

I'm wondering if someone re-wrapped a rocker II drum set. Those rocker II drum sets had a speckled interior and were pretty cheap. I don't think I would invest too much into these myself....

https://reverb.com/au/item/825479-ludwig-rocker-ii-1986-white