I have a used but still functional (though not at high capacity anymore) FP2 battery to give away for free. If the phone is used, they still last 4-6h.
Let me know if you like to have them.
NB: If you are interested and want to send a direct message, you will have to be a basic user on the forum. Reference about how to become one and other trust levels can be found here.
Be aware, that shipping batteries cross-border is virtually impossible for individuals.