From my research the rear pads on the Type R are unique to this car. You will have to buy from Honda. I believe Endless have made some but they are very hard to find. I have ordered the AP Racing brake package on recommendation from a brakes and suspension supplier/installer whom are supplying & fitting the Endless pads to FN2 Type Rs being used in the Indy Car Race on the Gold Coast (Queensland, Australia).
I will be receiving a set within a fortnight. Let me know if you want some and I'll find out some pricing?