Minwax and Mohawk make them. Mohawk supplies the markers for a few cabinet companies in their touch up kits. Color choice is another matter. Might be easier to buy a 1/2 pint or two of stain and use a q-tip or an artist brush. You can mix the stain.
As Ron said color is the key. I do furniture repair and have many markers. None of which seem to be an exact match :-) . I have better luck mixing lacquer to the needed color. There are markers (cheap ones) that come in light or dark color. These seem to work better than trying to find the exact color in a pen. I don't know where I got these two "light dark" but they seem to work better in masking scratches for the DIY crowd.
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