Hi!
You have to get the manufacturer of the top rail first. You may end up wasting your money purchasing a top rail that is not compatible with your above ground pool. :D
Also, be careful with using pool chemicals such as chlorine. Contrary to popular belief, plants can not neutralize chlorine instead some plants die around a chlorine treated pool so be careful. ;)
Not a bad idea, but if you want to revive it, I would suggest rent a pool pump and install solar pool cover.
You can save money and energy from pool heating with a solar cover.