This original version of Apocalypse Now was released in R2 (same spec as the R1 disc) around 18 months ago (or longer) now. I'm suprised you couldn't find it as it's been available from all the high street and internet stores ever since its release.
Apocalypse Now Redux is probably what the staff were thinking of when they told you it wouldn't be released until 2002, although the R1 version was released last November.
Redux is not necessarily a better or improved film just because it's longer, infact, it lessens the impact of the original cut, but it's still a good film and worth a watch or ten if you're a fan of the original version.
As for the ending with the explosions behind it...I'm glad someone else remembers this one. Nobody ever believes me it existed, but my mum's got it taped from it's first TV airing on BBC2 about 18 years ago and although it's not the big destructive bombing you see as a deleted scene on the (original version)disc, there's definitely explosions behind the end credits. It's the only time I've ever seen it, it's (AFAIK) never been available on any home video release. But it did exist, just the same as the film was released on video in 2.35:1 widescreen, I know because I've got it, although following widescreen releases always came as 2.1:1. And 2.35 looks so much nicer.