Railroad Paint Code Match Help!

So, let me ask: Are you searching for paint to match what's seen in the picture, or for paint that matches what the prototype used?  If the former, you might try contacting the model manufacturer; if the latter, you could try contacting the pertinent railroad historical society.  However, due to changes in paint formulations over the year, you might be running a fools errand.  My suggestion would be to look for model railroad paint charts on-line, find a color that approximates what you are looking for, and then use the proposed paint or paint mixture to get "close enough."

Chuck