Apologies for the short notice, but Bundle of Holding is just wrapping up a Pendragon themed month...
All the really useful 5th edition books are available as PDFs, including the Great Pendragon Campaign and the Book of Battle, plus the main 5th ed. rules.
Why is this of interest to Tekumel Gamers?
IMO, Pendragon has potential for use as a system for Tekumel games. And the Book of Battles has an interesting take on how to run a battle within an RPG.