Smith Boiler Touch up paint.

Greetings,
I am a service tech that takes care of a fair amount of Smith sectional cast iron boilers. I have just about pulled my hair out over trying to locate a source for some touch up paint for the light blue shell around the sections. Nothing matches quite right, and Smith and their Reps have not been helpful in my search.
I know that you can purchase cans of touch up paint for Fultons from their reps. I want to know where to find something similar for Smith boilers