Duplicolor T090 Truck & SUV Universal Black with a top coat or two of Krylon flat clear is a 95% match to original Dark paint, just a little more sparkly.
http://ducatimonsterforum.org/index.php?topic=29.msg398534#msg398534I painted my SBK front fender with this and it's holding up well after the first season. I recommend some dark primer to, otherwise you need lots of black to get coverage.
Scott