The TV series of Logan's Run and Planet of the Apes are reasonably obscure because they weren't too popular (I've got hold of both them, by the way).

Some other titles to pique your interest:

1981 BBC version of The Day of the Triffids

1979 Tales of the Unexpected (not scifi really)

1979 Sapphire & Steel (with the most annoying introduction - they are not elements!)

1979 Quatermass series

1979 The Omega Factor

1978 Blake's 7 (should not really count as obscure due to the impact the series had)

1977 The Fantastic Journey

1977 Children of the Stones

1977 Beasts (anthology series by Nigel Kneale)

1975 Sky

1975 The Invisible Man (really cheesy, featuring David McCallum)

1975 The Changes

1974 Zodiac

1973 The Tomorrow People

1970 Timeslip

1969 The Owl Service

1968 The Champions

1966 The Time Tunnel

1966 Mission: Impossible

1965 Out of the Unknown

1960 The Strange World of Gurney Slade

1958 Quatermass and the Pit mini-series

1955 Quatermass II

BBC version of the Triffids is legendary in my book. Don't forget 1975 BBC show Survivors.

I had to buy The Survivors on DVD because no one was seeding it, and no one was streaming it, either. I wonder how common that is for obscure TV shows?

Where do you find these seeded? I only know about Pirate Bay and 1337x.

I found season 1 of The Survivors easily enough, although it looks like season 3 might be available as well. I use prowlarr (https://wiki.servarr.com/en/prowlarr) which searches a big list of various sites and integrates easily enough with qbittorrent.

There's a handful of old British TV that I've bought on DVD because I couldn't find anyone seeding it.

(Just bought the three seasons of Survivor on DVD now)

Thanks for the prowlarr tip. Enjoy The Survivors! I did.

I do happen to be a John Wyndham fan and try to track down adaptations, and yes, the BBC one is the best (I remember watching it when it was first aired). The newer remake with Eddie Izzard was disappointing. I'm often surprised that his stories don't get more adaptations - where's Kraken Wakes and The Chrysalids? (Chocky was made into a good kids TV series back in the day).

I hadn't heard of Survivors, but that looks right up my street. I used to be massively into Doctor Who and the Terry Nation novels. I can only find the first season easily.

Have you tried BritBox? Some of those shows are available legally on there.

No, I haven't tried it. Being a subscription service, it kind of proves my point that even BBC shows financed via the TV license payers (including me) are now being locked behind paywalls and the more obscure ones will just disappear. (To make that list I just pulled some titles from my TV series library, so I don't need to locate any of them).

Two more entries for your really nice list:

1976 Gemini Man [another Invisible Man adaptation]

1976 Star Maidens