Items that come with an effect like this would be no drop and would only come from uber-mobs seen only by members of uber-guilds. So if you're after one of these items get ready to play at least 4 or (more like) 8 hours every day, seven days a week, raiding with a guild, after you spend hundreds of hours getting to the point that you would be acceptable as a member of such a guild. Going through the web pages published by these guilds you find that it is not uncommon to have members that have logged over 2000 hours a year on raids . That's as much time as most people spend at work every year.
I sometimes wonder why SOE spends so much time developing content that only a few hundred players out of a hundred thousand will ever get to enjoy. Not that I don't appreciate it as an admirer of lore of the game, but it seems like an odd thing to do from a business standpoint.