I am not sure of the guidelines regarding a living donor outside the country but I imagine your SSN would have to be listed in the UNOS registry to be eligible for the 4 extra points a donor receives in case they need an organ. Go on the UNOS wesite and there should be an information number to call to receive accurate info in writing.
Since each country has their own waiting list it makes sense that you would be eligible in the country you donated in. In Israel they now are trying to encourage more people to sign their organ donor cards as decesed donors and give the incentive that if you sign on you or a close relative moves up in the list. see this article
http://nofryers.com/with-an-adi-organ-donor-card-the-life-you-save-may-be-your-own/The life you save may be your own
Earlier this year, Israel enacted legislation to encourage increased signups for organ card donation. What’s the incentive? When you sign up, if you, your spouse, your children, your siblings, or your parents ever have the misfortune of needing a transplant, you’ll be given priority and bumped up the line.
The Law grants priority on the waiting list to the organ transplant candidate holder of a donor card before other candidates with similar medical data who do not hold such a card.There are actually three categories of priority:
‘Maximum priority’ is given to
those who they or their first degree relative consented to organ donation from a deceased relative
those who they or their first degree relative have actually donated (a kidney or liver or lung lobe) to a non-specified recipient
‘Priority’ is given to those who hold a donor card
‘Second priority’ is given to those who do not hold a donor card but who have a first degree relative who does
Children under 18 are an exception. They are treated equally regardless of the above priority system.
What it means for you is that if you and someone else are both in need of an organ transplant and have the same medical criteria, if you hold an organ donor card and the other person doesn’t, you’ll get the transplant.