I remember going to that shop a number of times and not only was it cramped but I remember it being rather dusty as well with all sorts of books stuffed into racks.
These days the shop off Leicester Square has improved the number of people you can now fit it there by adding a second floor...
Solar Eclipses happen a bit on Earth, so rather than realigning the heavens for an eclipse where the mage is located, the mage might find themselves moved to the next occurring eclipse on the planet.
Another vote for John's "Apocalypse Trilogy"
The Thing
Prince of Darkness
Mouth of Madness
And the thematically "All based on the same source material"
Miller's Crossing
Yojimbo
Last Man Standing
The whole UK collection is archived here
https://www.nationalarchives.gov.uk/education/resources/public-information-films/
There are some horror stories here along with some interesting social history.