As far as any of us know, there is precious little demand for through-hole LM308 chips, apart from the HUGE Rat market, which clearly outstrips iPad and Samsung Galaxy sales, and pulls in billions more than Hyundai and Kia together.
Sarcasm aside, worry about "fakes" when there is a sufficient market and sufficient profit margin to justify their production. These are devices in very limited demand, that sell for peanuts, and likely have NOS supplies that we WISH existed for Panasonic and Reticon BBDs. Is it possible that some of these supplies are still around because they're "seconds" in some sense? Yeah, I suppose. But there is NO economic justification for relabelling or otherwise faking LM308s, any more than there is an economic justification for cranking out counterfeit pennies.