The shade of green for CIE locos was standard, and the thirty nine other shades were on plants and women's clothes!
Often, as in GNR blue, lack of information leads to rumours that there was no standard. For CIE standard green, there are several accurately paint preserved buses, plus 800 in Cultra, and the mounted "flying snail" in Headhunters railway museum in Enniskillen. The latter two are actually painted with "real" paint Inchicore.
I can't comment, though, on reference numbers or the like. If the above real examples can be matched, that's the correct way to go.