Mike 16.
If you read the entire thread, you will see some folks have done the primary research, including letters from the Irish ministry of defense archives. There is a paper trail on these rifles, both in terms of acquisition records and disposition records. The official published letters from the MOD say 50,000 were purchased. the disposition/sales records say 49,000 were sold between 1991 and 1996. Both sources are Irish army Archives.
What Capt. Laidler is saying, and considering that he has been at the heart of the British MOD system for something like 50 years when the good captain speaks most of us listen, is that this information is wrong. He has not elaborated on exactly why but has stated that serial number lists he has seen back up his contention..
Given that the number of Brens to rifles should be at a rate of ~10 to 1, and the Irish only bought ~ 2,000 Brens, and retained ~10,000 SMLE until circa 1984 to 1987, it does give one pause with regards to the official published 50,000 figure of No4 Mk II rifles procured. 2,000 Brens to 60,000 rifles seems kind of off.
In any case the final declaration of truth will come between 2021 and 2026, when the Irish archives will open the records on the sales and the serial number lists will then become available.