(I'm not even going to mention the complete rights cluster-duck that is Monkey Dust (and yes, I've already got a copy of all the series))
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
Where do you find these seeded? I only know about Pirate Bay and 1337x.
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)
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.
1976 Gemini Man [another Invisible Man adaptation]
1976 Star Maidens
Can't find that anywhere though I was hopeful that BFI might have had a copy: https://www2.bfi.org.uk/films-tv-people/4ce2b80e92d21
FYI: https://rutracker.org/forum/viewtopic.php?t=5940948