Very interesting rifle! I wish I could offer some ideas, but I really have no clue as to it's origin. I do have some pics of my CLLE Mk I. Mine began life as a BSA & M, MLM Mk II. It still wears a properly cartouched Mk II stock that is NZmarked. However, I believe the NZ mark was applied well before the CLLE conversion. No other NZ ownership marks. Barrel and bolt are mismatched, and it carries British
proof house stamps as well as DP stamps. Enclosed are the pictures of the important areas. Note the grove cut in the charger bridge to allow for a proper sight picture.
again, yours is a nice rifle; I'd love to own it.