The domain name JOHNPAULIII.COM is available for sale on AfterNic for $1950.  It was registered in 1999.

POPEJOHNPAULIII.COM re-directs to  It was registered this past January.

Names such as Lando II, Formosus II and Agatho II, papal names not re-used, in one case, since 681, are still available.  Hat tip Volokh.