Theres a Diamond silver and Atlas grey metalic, both very nice colours
You shouldn't really pay much more for a MK2 just because its a 'rare' colour, unless its mint. But you would obviously be willing to pay more for a colour you like, over one you don't.
You like Royal Blue eh? Good choice, I picked mine up for £375, but it was a total shed. This is the day I bought it, and is the only pic I've managed to take which captures what Royal Blue looks like, its almost black in some lights, and a deep blue in others. Very nice, and very hard to find pannels for