OK Phillbob time for an answer you have been waiting long enough!

The answer is yes components from the C-130J program like engines could be crossed over into a p-3 replacement/refit program. Further from that Lockheed Martin did indeed propose as such more then once.

Read this article and ye shall have your answers!

http://www.flightglobal.com/blogs/graham-warwick/2007/08/p3-to-p8-an-airsea-saga-1.html