Can anyone tell me how much a replacement birth certificate cost in the 1960s?
I’m assuming you mean in the UK. The cost then was One Shilling and Sixpence, plus the cost of the search fee which was necessary to do to find details. Large, hand written, ledgers were kept at Somerset House, Strand, London (which in those days was the National Register Office) which you looked in (by year) to find those details. You could, of course, go to the local Registrar of Birth Marriages and Deaths if you knew the town were the birth had been registered.