My L1A1 (that's the black thing in the middle of the photo, the white thing it is on is an Icelandic horse...) was built in 1960 by the Royal Small Arms Factory (RSAF) Enfield. As you can see it has an evil® pistol grip, a polically uncorrect© buttstock with no thumbhole and a nastytm flash eliminator. In short: it looks like the British Army and Dieudonné Saive wanted it to look.
It has the following markings:
On the breech block's right there is a (rude) engraving of two crossed flags followed by
21 and 26.
On the left there is a marking S29 58 followed by 
960-2104.
The breech block assembly is marked on the right with UE 63550
The inside has S20 58
909516227.The top has
60 960-2107 and a very unclear picture of a crown above iK (?) with two crossed swords (?) below.
On the bottom trigger housing where it goes into the butt stock there is
 | ||
| ||
| 4 | 70 | 7 |
I couldn't find any other markings apart from some loose numbers here and there on the trigger housing which I don't think are proving marks. All parts that are serialized have the same number; i.e. this is not a kit but an original.
kees.huyser@nikhef.nl