The issue was this...
What stood out for me was that the art was that the art was clearly by Joe 'Charley's War' Colquhoun. An advert in the back for a reprint volume dated 1963 gave me my first clue for helping identify where the story came from originally.
Back in the UK and some chatting with Commando fan Colin Noble and we narrowed it down to, basically, one possible picture library. We narrowed it down so quickly because Joe didn't do much work for the picture libraries in the early 1960s.
The only fly in the ointment was the French title, Point d'appui, which means 'fulcrum' rather than Flashpoint.
Colin helped identify that the Flashpoint story had been reprinted a few times over the years...
Here's the original Air Ace Picture Library #35
Which was then reprinted as Battle Picture Library #814
and then reprinted again as War Picture Library #1639
Colin's info. was coming via the Fleetway Picture Library index volume 1 (the war libraries) by Steve Holland and David Roach.
This excellent volume also credits War Picture Library #1342 as being a reprint of Air Ace #35
but the cover makes it look more like a naval story than the desert based story that Joe had illustrated. Instead, War Picture Library #1342 (interior art below)...
...is a reprint of Battle Picture Library #611 (see below)
(original art for sale here)
...which is itself a reprint of War Picture Library #95 with art by Gino D'Antonio, script by RP Clegg and cover by Nino Caroselli - image below taken from the War Libraries index
Interestingly the cover for Rapaces #45 is actually from...
...War Picture Library #/868...which reprints Air Ace 62...
Interior art by Solano Lopez and a cover by Nino Caroselli.
And all that from just one comic.