Topps Stocks 1968-1970

[mets1986]

I have cards from these sets that feel thinner than others. The backs tend to be lighter, but the fronts look the same. Plenty are commons, so I'm skeptical these are counterfeits. Still, I'm not sure these are authentic.

I'll try to get better images of the pictures below, but really my question here is less about my specific cards and more about history. Has anyone ever heard of Topps mixing up the stocks they used in those days? That might explain why these cards look the same but feel different. I've been able to connect with Dave H. and others, and there is some consensus that the cards are real even if they're weird, but no one is really sure so I figure to do some more crowdsourcing here.

Or, if anyone has ever encountered cards that fit this description, have you gotten them graded? What does PSA say in this case?

Thanks very much to anyone who can help solve this mystery!

(In these pictures, the suspect cards are the 68 Brock, the 69 Brock on the left, and all of the 70 cards except for the Cesar Tovar in the top right.)

https://ibb.co/qNf7Bp0
https://ibb.co/svrwJgw
https://ibb.co/cLZsDsx
https://ibb.co/mGN9gWY
https://ibb.co/KjX0m4s
https://ibb.co/kc06yV8