I don't know the answer for certain, but I can tell you that finishes such as Enduro add a slight amount of dye in their formulation for clear polyurethane. Many pen makers I know use Enduro as their finish for just this reason, that the dye adds a bit of color, or pizzazz to the completed pen. This product might give you just what you're looking for. My knowledge of how to do it yourself is too limited to be of help, should you go that way. If you decide to do so, please report your findings, as I am sure many of us will be interested in how it turns out.