Pink Floyd sound can easily be acheived with; A Hiwatt Lead 100, my Burns Batwing, a ProCo Rat and a Roland Stage Echo tape unit.
Seriously though, you should get close with a decent crunch sound on any amp, a good echo/delay unit, a single-coil equipped guitar and a Rat, or any other good fuzzy distortion pedal. And then it's down to experimenting. Bear in mind on Animals there was a bit of harmonising too, so you'll never get amazingly close unless you have a friend playing the other bits too.