Axles for the floater rear are usually the responsibility of the end-user... At least they were when I got my kit nearly 3-years ago (wow - time flies). Axles are available from Speedway and are "off the shelf" with, for all intents, zero lead time unless you have some radically odd rear end width.

And +1 on the R-Spec rotors - they are awesome. I've had them on the front for a while and will be adding a set on the rear here shortly. Brake solutions sure have come a long way in a short time.