Hi I have new genuine W & S stock insert discs if you want one e mail me at ray210645@yahoo.co.uk
Your rifle was made in the last week of MKIII production; it was in block 1 of the last 12 blocks of ten; [F6461 -6470] made W/E 6-12-1975
It is listed as .22 cal and was made by David, second senior hand on the section. Therefore it was made Monday 1-12-1975.
Info is 100% correct from actual bench handbook not Webley records [Chris used this info in potted from in his book]
Hope this is helpful
abellringer