The definitive answer to this is on page 213 of Steve Raw's book, in a picture of the Enfield Competition Rifle, basically an LSW with the gas block blanked off, single shot, fitted with a modified Cadet cocking assembly. You can see clearly from the photo that this rifle is also modified exactly the same as mine and the other two mentioned above.......and Peter confirms this rifle was obtained new, directly from the ROF Enfield factory modified in this way, which concretes the provenance of these modifications. [David TS]
Vince Bottomley (aka 'The Gun Pimp' here) was loaned one of these and reviewed it in the old 'Target Sports' magazine getting on for 20 years ago now. (Our man Vinnie was a Practical Rifle competitor back in these days before becoming a Bench Rest and F-Class guru.) I suspect that would be post-ROF Enfield and by then BAe Nottingham, but Vince can no doubt say which if he reads this. The guideline price quoted was really attractive compared to SGC Speedmasters, and I remember thinking, I'll have one of them when they appear - but, of course they never did! Whether that was due to truly commercial reasons, or whether a result of political pressure is debatable, although I know whcih side my money would be on.
PS I also have Steve Raw's book. Fascinating reading, and really depressing too! When I mention it to people, nobody I speak to has even heard of this book never mind read it. As our former colonial cousins across the Atlantic say, an elephant is a mouse designed by a government committee.