Even if @zenvelo‘s apt comments can be overcome, the answer is still no.
A doctor – at least in the USA and most of what we consider the developed world – signs onto the Hippocratic Oath before beginning practice: “First, do no harm.”
Cutting into a healthy person’s body – even with good intent for someone indefinite in the future – causes harm. Doctors can absolve themselves of that restriction when they cut into a healthy organ donor (kidneys, in particular, but now also liver sections as well, and mabye more in the future) to obtain a healthy organ for transplant. The thought is that it is a genuine life-saving (or hugely life-improving) operation to aid another patient that is known by the donor, so in this sense it’s a collaboration between the surgeon and the volunteer / donor to save the life of a particular person.
If the proposed implantation was “indefinite” for “no one in particular” and at “some time in the future”, there would be too much potential for abuse. I doubt whether any legitimate medical organization would sanction such operations, ever.