FWIW, and it really isn't worth anything, I contacted the manufacturer to ask about the color. Here is the reply:
"Unfortunately, we do not have the CMYK or RGB color codes and we do not sell touch up paint. The actual color code is something that could be determined by scanning the wheel at an alloy wheel repair shop.
We recommend the brand Dupli-Color for DIY touch up paint. It is readily available at many stores. Some of our customers have had very good results mixing their own color match and testing it bit by bit."
Not helpful to me as I am not an artist and I would not have much luck trying to match the color on my own. It also isn't helpful to take a rim to a wheel repair shop as that defeats the DIY aspect of the thread. If anyone does mix a color that comes close, though, please share.