There's no easy way beyond using them. Given the unique design of the ICs, I don't think there's other similar ICs that can be rebranded as this.What would you look out for with respect to identifying that these were legitimate versus being fakes? If they pass capacity testing it feels like the most likely misfortune would be cleaned up pulls versus new stock, at least in such case they'd be functional.
The only issue you might run into is if you ordered 1Gb chips and got 256Mb chips.