In terms of cloning PEOPLE for organs (a la "The Island), I think that is taking things too far. Unless we are talking cloning Ewan McGregor (a la "The Island"); I can make a case for that.
But creating new organs for the same person? On the surface, I can see that.
As far as living 1000 years, imagine how densely populated this place would be. I will settle for living a healthy full life, and going in my sleep.