Doesn't the BBC offer a service where you can request recordings of any historic broadcast?
The German public-service broadcasters like ARD, ZDF and many regional ones offer such a service. I can request a program from the 70ies, tell the name and (helpfully) where and when it was broadcasted. Then they search through their massive archive, make a copy on DVD and send them to you. It's not cheap (up to 40€ per hour of program), but it is legal for personal use. No need here to pirate anything, except very very old broadcasts from before ... around 1967.