Thank you very much Kgambit, I though the same thing about not being a combat unit.
The only information from the person who sold me those photos are:
"PARRIS ISLAND SC F6F Hellcat Fighter 1945 SNAPS" but as we can see, those plane are not Hellcat so I'm not sure if I can trust "PARRIS ISLAND SC " too ...(didn't post at first to avoid misleading)
If the Official Monogram doesn't give the information wonder where the answer could be
Will post other scans as soon as possible, may be they will give us more clue?
Many many thanks Kgambit,
Olivier