Is it possible to make armour that can survive /kill?
No, it is not.
The /kill command dealt "void" damage before the introduction of the instant kill. Because the protection enchantment or the armours base protection does not reduce damage dealt from the void you would still be killed.
Even with modded armour with high protection or 32k enchantments, this would still be impossible due to the fact "void" damage ignores armour.