I suspected it was a F-4 Version of Lightning as I could NOT find any P-38 Fighter Units based at Espiritu Santo, New Hebrides
Howabout (purely as a suggestion requires further research)
http://www.joebaugher.com/usaf_serials/1942_5.html
Lockheed F-5A-3-LO Lightning
42-12772 scrapped at Espiritu Santo, New Hebrides Jun 15, 1944
MSN 122-7206