Nothing ever matches up to new original stuff but I have used (pinball decals eu .com) and his stuff is good even with shipping to the USA it’s well priced. He does custom stuff….which he has done for me…twice.
To speak to black on an Earthshaker - the blue in Williams machines like Whirlwind or Whitewater which I have tried to match paint on before, blue is an impossible color in shades when it fades, black is easier to do match. I did a Black Data East LW3 with new decals and it looked awesome. It’s not wrong when you decal your cab to repaint the whole think anyway but the blue is just a hard match. I wasn’t happy on three blue machines I have redone with any of the blue colors I used except when I repainted the whole thing with a match to the decal which I brought in as the color sample.
If RadCals were available for this pin I would go that way but they are not.
My tip as I explained above is for you is to order your decals and then take the decals to a paint store for the best paint match to the blue of Earthshaker (unless you go with Black Earthshaker decals which the site I recommended will have).