I think you missed the point, it was said that if the situation was desperate, this could happen, or if the situation was urgent, Buying new, the equipment is years away and if you need it now re-activation is always an option.
TBH I think that the hypothetical scenario raised is more, it might be able to happen, and reactivation might be an option.
Much would depend on what the actual conditions are for both the aircraft, and the avionics. If there is too much fatigue in the airframes, too few parts available to support the mechanical components, or the avionics are too far shot and/or removed, then retired P-3's would not be reactivated.
One needs to remember that the Kiwi P-3's were originally P-3B's delivered in the mid-to-late 60's (IIRC one of the Kiwi P-3B's was gotten second hand being an ex-RAAF P-3B).
One of the Kiwi P-3 upgrade programmes run during the early-mid 00's updated some of the avionics and re-winged the aircraft. However, IIRC when they were re-winged the new wings were not wired with the then current MIL-STD databus, which sharply limited the options available to make effective use of ordnance from Kiwi Orions.
If the avionics are still good, and the aircraft themselves are mechanically sound and in flightworthy condition, then they might provide some usefulness for broad area maritime domain awareness.
