I agree with and will defer to Rusty on this. Thanks for the tag @nikhil, but I wouldn’t consider myself an expert on vintage sealed product.
From a lay perspective, I would think that these are real. I don’t see any glaring evidence to suggest otherwise.
The one small difference that I can see on the Blastoise pack is that it has a very slight offset printing, which makes it look a little odd and messy. That is normal variance from Base Set, as far as I can remember. The energies on the back of the packs also look a little washed out, but that could be the lighting or unique to the specific print facility that printed and packaged these. There is just so much variance in Base Set.