Thanks for that PrinzEugen - the scope mount has the same number as the rifle so that checks out.
The "new" scope's serial Number is punched on the gunstock just behind the action & just below the XXX'd out previous scope number - which i assume was a Mk3.
It's not usual to cross out the old number and punch the "new" scope serial number on the stock ? most would just leave it as a miss-match ?
Got me confused !
But the Mk1 is an inferior scope to a Mk3 .( and a bit cheaper to replace i suppose).
Thanks for your comments !

---------- Post added at 04:50 PM ---------- Previous post was at 04:45 PM ----------

Thanks TB
Looks like a re-assembly job i suppose. But as i posted to PE why bother obliterating the original scope serial number and stamping in the "new" old one on the stock ?
Would a military refurb replace the scope with an old MK1 ??