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Amazon has quite a few listings, A fellow Redditer suggested me the 2 disk "special edition".
It has the original cut of the film, and quite a bit of special features.
Good price too!
The Manga Special Edition DVD from 2005 is probably your best bet:
There is a "25th anniversary" Blu Ray release, however apparently it suffers from problems with sound quality and subtitles. So, as usual, the only decent way to watch the original version in HD is to become a pirate.
[The 2017 movie with Scarlett Johansson](https://en.wikipedia.org/wiki/Ghost_in_the_Shell_(2017_film\)) is a really bad remake of the [1995 anime version.](https://en.wikipedia.org/wiki/Ghost_in_the_Shell_(1995_film\)) Unfortunately, you can only get the 1995 version on DVD; no Blu-Ray. Amazon link. Also, if you go to... certain... websites... you can download a 720p version of Ghost in the Shell that's great quality overall.
There's a "remastered" version floating around called Ghost in the Shell 2.0, but it's a lot worse than the original. For some reason they made everything orange and added a bunch of cheesy CGI.
(Also there technically is a Blu-Ray version called the 25th anniversary edition. But they messed up the subtitles and the audio pretty badly.)
Edit: Reworded everything because it's 4am and my comment was really confusing.
Some nuance on what /u/Bebop_16 said: newer Blu-ray releases of old anime sometimes take a step backwards in Japanese audio quality or special features. For example, the old Special Edition DVD of GitS had 6.1 audio for Japanese, whereas the 25th Anniversary Blu-ray edition had only stereo.
There are also some SD Blu-rays out there too, and others that were badly upsampled from SD sources or "remastered" in ham-fisted ways (Disney's early Cinderella "restoration" was an infamous example!)
Don't get the wrong idea that you should avoid Blu-ray versions of old movies – there's some amazing restoration work going on in the industry – but Blu-ray > DVD is only a rule of thumb, and it's especially difficult for something like anime both because licensing and source access get in the way and because fans consume the same optical media very differently (subs or dubs? SDH? what's your home audio setup? etc.)