Is there anywhere else in any of the world's top clubs?

I think not.

Joe Hart

hmmmm

Ospina
Hart

this

You've both clearly haven't watched Joe this season, it has probably been one of his best seasons, sure he makes mistakes, but not nearly as many as Casillas.

Even Caballero is a better keeper than Casillas right now, which is a real shame, because I grew up loving Casillas, I've seen him play live and spoken to him so he was always one of my favorite players.

mignolet (yes i know he's in decent form atm but we're talking about overall quality here)
weidenfehler

weidenfehler nice

Disagree on that, Mignolet performed for a few seasons in a row despite being so young, one dip of form does not mean he is a bad keeper.