Action or script to replace color range in multiple documents?

I'm editing a few hundred PNGs for a game. I've managed to automate a fair amount of the proicess that I need to do.
I'm hoping that I can also automate one more thing, as I see it as being within the realm of possibility. However, I don't know how to go about it.
I'm replacing the color of a character's blue eyes with brown. 
Basically I need to select a color range, or multiple colors, as eyes obviously aren't a solid color. Then either hue adjust those colors, gradient map them, or selection to layer > replace color > blending mode: color or something/anything to that likeness.