What I did in this particular instance was do a Google image search for a suggested color, example Humbrol 73 for the mandibles. You can usually find a picture like this:
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It gives you the Hex # and the RGB code. You can then go here:
You can enter the hex code at the top and cross reference the color with different brands of paints. It gives you the name and code of the paint that most closely matches. Behr and Valspar are on the list, which you can get at Home Depot and Lowes respectively. That is how I’m doing it. It may not work in the end, but this whole thing is one big experiment. Here are some other useful sites I have been using for my “experiment “.
RGB color codes chart, RGB color picker, RGB color table.
www.rapidtables.com