John,
Rifle number A426 is recorded as having been sent to store at Donnington on the 20th Feb 1970.
Rifle L32431 was part of batch number 70 which consisted of 13 rifles. Records show a conversion date of 12th November 1975, upon completion it was shipped to store at Donnington.
Ahh yes Ma Parker's shop. She had an ancient dog with cardboard ears and the place always had a peculiar Ammonia smell if you catch my drift
Cheers,
Simon.