Leper Joe in The Darkwood sells level 61 Prophetic Rings on Legend mode with +15% to magic find or level 27 Oracle Rings on Heroic mode with +9% magic find. It's possible to keep logging in to get these rings.
He's located just before the Darkwood Graveyard, so the fastest way to get to him is to enter The Darkwood from the Gothicus Gates area. Sometimes the magic find attribute will be replaced with something else. It seemed to be about a 33%-50% chance he had the ring in stock (he only carries one at a time).
This might be a Warriors only hope to increasing Treasure Finding since their gear never includes magic find.