nobody is going to be stuck in their 80 years old body.
this is the extremely short version/recipe to leave forever:
1. clone yourself. work with this guy who is very close to succeed [1]
2. once your clone is 25 years old and therefore stop growing, undergo a brain translation. Now, before you start laughing look here: [2] This is Dr. White [3] undergoing successful monkey brain transplantation in... seventies! I think 40 years later technology got much more advanced.
So the result would be your 80 years old brain (assume it was still quite healthy) in 100% matching DNA body of 25 year old. IF you don't get brain cancer, or other brain disease, you have another 50, 80 years to go. Now, going further only certain parts of the brain makes up for your identity. Most likely only memory. Fast forward another 40 years in the future, knowing how to connect broken nerves again why not cut only small part of your brain that is you therefore transplanting only your identity and limiting size of your old body in the new one.
Now, you can call me a conspiracy theorist, but if to overcome problems here is just a matter of time (by that I mean more time == less money + less engineers working on the problem. less time to resolve problem == more money to throw at the research + more engineers working on it), then I believe it is fairly plausible that elites like Rothschild family having billions of dollars for their disposition already have these technology available. Just ask yourself -- if you already have trillions in the bank, and building another successful company or buying another factory is boring to you AND the same time the only thing you are sure of is that one day you are gonna die, then it is obvious you will spend all your resources to "postpone the judgment".
[1] http://en.wikipedia.org/wiki/Panayiotis_Zavos
[2] http://www.youtube.com/watch?v=xb3Zi0DenaE [viewers discretion advised]
[3] http://en.wikipedia.org/wiki/Robert_J._White
* I didnt want to go into the obvious legal issues here: cloning humans, "stealing" someones body, putting another "human" in 80 years old body therefore shorting their life, etc.