I don't know (so I need to research, huh?) if they were standard on Slingerland Concert toms. However, it is my understanding that the Remo CS black dot heads were originally manufactured specifically for use on and as standard issue on Pearl's concert toms in the mid-to-late 70s. Then at least by 1978 they were standard on all of Pearl's fiberglass and wood/fiberglass drums.
My 1978 set came with Remo clear/black dot heads on batter and resonance sides. Remo heads but with the smaller Pearl logo...
And, for what it's worth, there is a seller on eBay that has some sizes of original NOS Pearl/Remo CS clear/black dot heads at some pretty reasonable prices. I'll post a link when I get a chance...