I'm using a 2006 Code Red 7.7m2 with a North Sails Viper Race 460 cm IMCS 25 mast with perfect results. The tapered diameter of the North mast (called drop shape) fits neatly with the cambers even thought 2006 Code Red don't have cam spacers.
Didn't tested yet how it works with a Code Red 2009 sail but I'm pretty sure it will match.
Red Line masts are not produced anymore and have been superseeded by Enigma masts as of 2009.
Severne sails european dealers can be found here :