You have a genuine Long Branch "T" backsight by the look of it - no one has faked the Maltese cross mark as far as we know. The rest of the rifle is a bit contradictory: it has been refinished and with some sort of black paint as well, suggesting the UK perhaps. The receiver looks rather rough to be a genuine Long Branch "T", considering those rifles were not selected from production by that point, but "shepherded through" production as batches specifically intended for conversion.
You MIGHT have a genuine rifle that was reconverted to regular No.4 specs at some point, hence the missing butt(?), and then later "restored" by the addition of a genuine(?) backsight and one of the Italian "C67" bases. The whole assemblage does not look convincing to me, despite the oddly highlighted serial number.
You might want to post photos of the serial number on the bolt and any other markings as well, preferably with the rear handguard removed.
It's also possible someone gave the rifle a basement refurb and refinish, thinking they were "restoring" it when all they were doing was destroying the patina and finish that might have proved its authenticity.
The forend has been sanded down on either side of the trigger guard to a strange and excessive degree - maybe Peter could tell us if such a forend would be considered acceptable for fitting?
Sorry to have to say that, but no point mincing one's words.