Recently discovered an American cornucopia of a site with vintage TV and Films and much more, which can either be streamed or downloaded. It's a sort of library where people upload whatever. There's also audio, books, images, software, apks. I haven't investigated these yet apart from some CDs, which were only 30 second clips. Although mainly American series, there is also some British ones. Anyway here's The Man From U.N.C.L.E. series 1, Police Squad with Leslie Nielsen (only 6 episodes ever made) and The Time Tunnel. Was going to include The Invaders, but it seems to have been taken down. The search engine isn't wholly reliable:

archive.org/details/television_inbox?sort=-week

archive.org/details/the-man-from-uncle-s-1

archive.org/details/s-1-e-1-a-substantial-gift

archive.org/details/the-time-tunnel

archive.org/details/LogansRunSeries