Without you dehumanizing some stage of life based upon your subjective whim, tell me when human life begins and ends.
My subjective whim is mine, but also is beneficary for all people. I don't need spare parts (at least not yet). There are many people, who need currently. If we are to be immortal, we all will need spare organs in the future.
Purely biologically the life of the human lasts from the zygote to the death.
The human life that maters - from the brain starts working until the last electromagnetic activity of the brain.
If you don't allow the human cloning for organs, do you allow it as a technology for eventual protecting and proceeding the human race? If the clone remains alive, it seems, that your main argument becomes invalid, right? How about cloning people, who remained without a child in order to proceed their ofspring? Here again your main argument stops working - the clone is alive again.
It matters only to you but not to those who die. You live only because you dehumanize others so you can rob their body parts. Nothing in Biology backs up your values and reasoning.