BJ, It'd be hard to compete with the rings...I give them away for free....but I am inconsistant (sometimes I have spare mdf, sometimes I don't)
But as for making specific custom rings...maybe a nice niche market. If you could make some that would fit my s-10...hell //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif