Well, I know that Jun Kusanagi had stuff released as late as last year - and she started in the mid-90's ('95? or '96?). That means she outlasted some of the mega-superstars in western porn like Jenna Jameson & Asia Carrera, who were contemporaries of hers.
Of course, she's retired and come back a few times, but even in her mid thirties she still looks good. Her huge, all-natural, G-cup titties haven't really sagged and her pussy is pretty and fresh-looking (gotta love the uncensored stuff).
Some of the other girls from her era have done a few one-off's - mostly uncensored - but I don't think they've really done more than that. I'm referring specifically to Bunko Kanazawa and Sally Yoshino but there may be others.
I'm still holding out hope that Akira Fubuki will make a comeback. She was one of the most beautiful of all time. Killer body, too.
I know, I know... keep dreaming, right?
-Nick