I know this is late but the early shows were most likely broadcast live, as with everything else of the period. The telesysnc's, as they were called, are either lost due to reusing the tape like John Lennon's death announcement on the Monday night football program or they were just destroyed or miscataloged.
The attic part is wishful thinking that someone/'s, somewhere had the forthought to "film", or rather record the broadcast from the television set on a home film camera (a seudo "telesync?"). Thus, the recordings would eventually end up in someone's parents or grandparents attic.
So go check your attic!