I'm too lazy to go chasing Endermen, so I want to know: Which guy from Villager deals with Ender Beads? I know that not every guy is always the same, but if I already trade a villager high, then it should be the one who has the highest chance to sell endowment beads.
As far as I know, the Bibliotheca, when it's high-level, sells Enderpearls.