If you go for an aftermarket clutch you will also need to replace the flywheel. The factory dual mass flywheel can only be used with the factory clutch.
As for aftermarket brands, Exedy is one that is commonly used. They make the TRD kits. ORC & OS Giken are a couple of other brands that spring to mind.
Flywheels, Im not sure if any one brand better than the other but JUN, TRD & Toda seem to be used/recommended a lot on the forums.
Just found this complete TODA flywheeel & clutch kit http://www.jappartsspecialist.com/produ ... ts_id=1322
for €630. Geuss it all comes down to your budget at the end of the day.