Sakamoto,
There are LDs of the Climax Files. I own them. They’re pretty good. Not the best Pink Pineapple stuff (as I think they were working on the Doukyusei 2 OVAs at the same time), but pretty good. The ending is kinda… well I didn’t like it.
Jungle might have some used LDs of it. That’s where I picked mine up. Some of the LDs even contained the extra cell art still too Woot! Omake!
As for the girls, it’s still mostly the girls from Doukyusei (Mai, Satomi, Misa, and Kurumi), but they add another girl, Shimamoto Kyoko (I think that’s her name), and a cameo by I can’t remember her name! GAH!
It’s the girl in Doukyusei 2 who is the main character (with the ribons tied in her hair that she won’t remove until she’s with her true love… I can’t believe I’m drawing a total blank on this…) anyway, she appears briefly during the Spring Carnival at the high school. She’s waiting for her brother to arrive, and Wataru flirts with her briefly.
Anyway, hope that helps some.