Does anyone know of an off the shelf readily available blue that is a good or close match to MRL blue? I would rather use an available blue rather than mix a custom color. Thanks.
That’s a good question, and I’ve wondered the same. So when you find out let me know. I just received two Athearn SD40’s in the mail of MRL and I’m just going to color match from them when I go to paint my SD45 from Kato.
midwestfan,
I just received your email, it didn’t have your email address so I couldn’t reply, so I will do it here. To be honest with you If you are like me and want these engines to look close to the prototype then it won’t matter if the color is a little off. MRL’s Fleet aren’t in the best shape anymore. I know this from observing them all from spending the time in Montana going to school. I got an A+ in Railfanning.
Here’s what I mean:

If I was painting up an MRL loco… I think I would start off with Santa Fe Blue (Floquil or Polly Scale, depending if you like enamel or acrylic) and lighten it up a touch. Should give you a reasonably close-enough shade. I wouldn’t worry about an “exact” match because no such thing exists-- Prototype shades often differ, depending on which shop the engine was painted at, weathering effects, etc.
As long as you don’t have to match the paint to the color of the decals (such as that of the CSX locos where you have to match the blue or yellow to the billboard CSX letters), the shade of the paint is pretty forgiving.
Good luck!