Hello all, I have two jackets that I believe both belong to the 1975 Hobbit published by Unwin. One is on a 1975 printing, and the other is a mismatched set of a 1972 text with 1975 jacket. On one jacket (75/75), the price reads £3.00 and on the other (72/75) £3.25. Was the price changed partway through the printing? As this was last printing of the 3rd edition, I know it can't belong to a later one. I haven't been able to find anything on this so I thought I'd pick your brains. Thanks in advance!