Everest 3 Battery - Borrow?

I am traveling August 27 and have been on the waiting list to receive a battery for my Everest 3. If anyone has one that I can borrow, rent, buy, whathave you, I would very much like to be able to use my CPAP on the plane (already have permission from the airline). I will be back September 12 and can return it then.

Anyone? Anyone?
Thanks!

Kai