Here's a link to Mohawk powder pigments.
http://www.mohawk-finishing.com/cata...asp?ictNbr=130 The one you're after is the 12-color kit, which may seem a little pricey at $93.26, but these pigments should last a lifetime unless you're going into massive production. These will tint or color just about anything. I've desired this set since I worked with it in the 79s when I had a job as a furniture service guy at Louis Shanks of Austin. Louis was a genuine Texas "good ol' boy" and had stories of LBJ, with whom he had grown up.
These pigments would likely work with JBWeld. The disadvantage to painting the repair is that the color would soon be worn from the patch. If the entire volume of the patch is colored, this problem would be solved.
Your repair will need to be opaque, so I'd blend in a solid white base of some sort to accomplish this, then adjust the hue and intensity of the color.