I have had no luck finding decals in 1/48 for these helicopters but I did start assembling the parts to make them. Even if I don't have the markings I will at least have some pretty colorful painted helicopters.
Here is what I have so far.
Japanese UH-60J pylons, tanks, tail rotor and main rotor assembly.

Taiwanese S-70C tanks, tail rudder, tail rotor and main rotor assembly.