Well there you are: Singer Manufacturing. The mark is also seen on Mk.I backsights and Mk.I "button" cocking pieces. IIRC they changed to another less obvious mark later.
In view of what I said before about value, that remark referred to an RSAF Enfield made example.
And considering how thin the tongue on that butt plate looks and the protrusion of the screw heads, someone has held it against the belt sander too long...which no doubt explains the missing nub as well.
Not trying to make a habit out of disagreeing with you rgg_7, but to me that looks like the original Beech set with the rear handguard swapped out for another later. I would assume that these early forends originally had grooved rear handguards as that was the first pattern was it not? The fluting was rather prone to damage and perhaps swapped out for that reason after getting beaten up during a few years of war service?
If this was a UKFTR would it not be marked as such?
The two groove barrel and two position backsight would not be likely refits in UK service would they? Therefore would they not be original - or else fitted in some other country.
Do I see a hole in the bolt knob Spaz86?