There's some tell tales on the body of the gun Peter. Only a Enfield intermediate gun would have them in the combination shown on that gun. I've attached a photo of E9905 and the gun in the desert photo, in red I've circled the rib on the RHS, the fluted gas ports and the dished gas shield. In blue I've circled the missing scalloped area in front of the mag well and the contoured section at the rear, as all original Enfield Mk1 would have these. From this I can tell that the serial number would have been between E1793 and F7532 and I believe I can narrow it down even more as I have listed 1940 E9534 which has its original Mk1 lower and 1941 F3335 which has a Mk1 modified ptn A lower so I believe the gun shown is between E9535 and F3334. Of course the lower could have been replaced later in service but it still has a butt disk and spoon, and hopefully you can tell me when they were omitted as I'm not sure but recall it being early 1941ish.
https://www.milsurps.com/images/impo...7743eaa7-1.jpg