I really, REALLY hope this thing is legit: that a toy company repurposed the mold for Vicious Volcano when the Flintstones movie came out in 1994 (one year before Sammy Steel was a thing), and made this cute little playset thing.
Presumably if it IS real, there were two, and half the figures are from the other set.
Even if it’s a custom job, it’s pretty badass. Haven’t been able to find the figures anywhere on their own, and I don’t know yet if I want to shell out what the seller is asking for it without knowing for sure where it came from (he WAS nice enough to let me use his photos, though).
EDIT: THEY’RE REAL! Just found a listing with carded sets being sold in France! Apparently Flintstones were extremely popular there.
Mike's Toybox 
not sure if you are looking to buy, I found a somehow almost complete set of this toy. contact me if you are interested