Most interesting Nige. Wish you all success in the loft!
I've found my photocopies of the SAC minutes from August/September 1917, which I'm afraid don't help on the issue of scopes graduated for Mk6 ammunition, but which state that at that time 350 Aldis scopes had had prisms fitted for lateral adjustment, & that the total requirement to be so converted was 750. At that time it seems as though it was envisaged fitting these scopes all to P'14's although the Hensoldt light telescope is mentioned in the text as well. I've also found some minutes from 1921 on the disposal of the SMLE snipers that were then to hand. Thirdly, I have managed to retrieve some data on the contracts, most but possibly not all of which is in TBS, on contracts to the various trade members such as H&H, Purdey, & so on. It is quite illuminating in that some contracts were awarded for 'the fitting of telescopic sights', & some for 'the SUPPLY & fitting of telescopic sights' (my capitals), which perhaps has a bearing on our earlier discussion. Unfortunately my printer/scanner refuses to recognize my laptop to send the files to, but I will try to get round it & as soon as I can I will post them here in case they are of interest.