Killer of Sheep is from Charles Burnett. It's an American independent film from 1978, highly praised, and a precursor to the work of Spike Lee. It was also selected by the National Society of Film Critics as an essential.

All the films on your list Sara are readily available, some already on DVD. The only long shot is The Passenger, which good news, it is recently being re-released in theaters. I'm not sure where this will lead, as I was convinced it would never come out on dvd, but theatrically it is showing. I do have a copy of the now OOP Japanese edition, so I'm at least happy. I will agree on The Virgin Spring. I stopped hunting out Bergman VHS because everytime I did, Criterion wound up putting out a much better version on DVD, so I just wait for them to get around to it, same with Kurosawa films.

Still from Bergman I want to see:

Summer With Monika (1951)
Face to Face (1975) - the full TV version, they did it with Fanny and Alexander and Scenes From A Marriage so why not?

As for Kurosawa I'd like to see Sanshuro Sugata (1943), and the Idiot (1951), I certainly didn't need another release of Ran.

The Devil Probably (1977) - Robert Bresson
Spirit of the Beehive (1973) - Victor Erice

I agree fully with the early Oshima and Immamura films, definitely some must sees from those two, and not a lot to pick from, even on VHS.

Top of my list of things to see are . . . 

Hour of the Furnaces (1969) - Solonas
A Brighter Summer Day (1991) - Edward Yang
To Die in Madrid (1963) - Frederic Rossif 
The Emperor's Naked Army Marches On (1987) - Kazuo Hara
The Silent World (1956) - Louis Malle, Jacques Cousteau
Kings of the Road (1976) - Wim Wenders
Satan's Tango (1994) - Bela Tarr
I Even Met Happy Gypsies (1967) - Aleksandar Petrovic

That's enough for now, I'll just go back to my corner and weep that these will never be released.