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Search this sub forum for vintage photo restoration - it seems like you're looking for the reverse situation. A member named theSuede had a nice piece on how to recover faded vintage photos that was particularly detailed and informative. Do it in reverse and it may help you.
The short version is that printing is a CMY process, and usually the C color fades fastest, leaving a strong magenta overtone. Convert your images to CMY and play with the curves until you get one that looks good, and you can save it (the curves, that is)