....
What edition/year of Ocean Passages am I looking for?

Well, I'm not totally sure about the edition history but I think that
you want the 2nd edition or earlier (ca. 1970 something) as they went
to a smaller format after that. The newer versions are treasure as
well but there is less to them. You might try http://www.amazon.co.uk
or other UK or Commonwealth sources as they are more likely to have it
and will also likely have better prices. Good luck.

-- Tom.