I believe there are some folks here interested in the history of the rules. I've been given a collection of RYA publications including appeals from 1966 to 1980 and 1987 and RRS 1978 inc RYA prescriptions. If anyone would like them you can have them for the cost of postage from the UK.
I got what I wanted from Andrew Alberti's excellent website https://www.yachtracingrules.ca/appeal-and-casebooks