If your looking for some custom discs with cast rotors, ISR sweeden will make a set up for you takes around 2 - 3 weeks from order, not cheap but then for an extra £30 - £50 a disc you get an awsome disc made for your bike, I remebr it was one of the things i was gona do before selling the bike and i was quoted around £180 / disc for Semi floating
here
http://www.p3unlimited.com/Disc_order_form.pdf
http://www.p3unlimited.com/brake_disc_orderform.htm
http://www.p3unlimited.com/brakes_overview.htm
And to top it all off the guy who runs the shop is an ex racer/mechanic so has an idea of wht you need.
Of course you could always try and source a second hand pair, alot cheaper!!!