I searched the forums and found an old post "Australianicon Coachwood fore ends without copper recoil blocks?"

Muffett.2008 wrote

The woodwork was passed over to Slazenger in November 1941, recoil plates were a standard fitment on Forewoods at that time still being predominately Qld Maple.
When Coachwood became the predominant timber, these plates were still being fitted, but towards the end of 1942 and into 1943, the practice ceased.

With the increase of failure of Coachwood stocks the practice recommenced mid 1943 and continued until the factory ceased repairwork in 1960.
Several different methods of repair were tried from 1930 on, the copper plates being the most cost effective.

The Jensen Report and Tony Griffiths volumes cover part of this information.
https://www.milsurps.com/showthread.php?t=60359

If it were mine, I'd have the plates fitted for peace of mind.