I had some Axial oversize rims (they are 40-series size) that had 17mm hex. They aren't dish, but probably just as light. And they were black. Look in the "Pay it forward" thread for pics, I sent them to Chadworkz but maybe if he hasn't used them yet he'll hook you up.
These are the ones, not sure about the offset:
http://www.rcplanet.com/Axial_8_Spok..._p/axi8008.htm