L42A1 (new to me), Rare Maltby Conversion

[Troglodyte]

https://www.milsurps.com/showthread.php?t=4098
This might be of some help?

Thanks. I have a hard copy courtesy of Brian Dick--it shows the parts in question, but my rifle lacks them. Was interested in learning how close to reality the catalogue is.

I have a lock washer, unsure if I can even find a seating plate. All of the other parts, to include the little spacer tube, are already present.