First guy that came to mind was Paul Pierce. The shot on Harrington was ridiculously awesome. Game 7 in '08 when he went head to head with LeBron in the 4th was crazy. The guy is still hitting clutch shots well into his 30's ("I called game"). Horry hit shots, but you can't compare him to somebody who is creating his own shot and has a defender draped all over him, knowing he's going to shoot it.
Ray is another guy. He made a LOT of shots, but he REALLY made them when they counted.
Both of them are miles ahead of Kobe in terms of clutchness if you ask me. Jordan and Bird as well. Curry might be a better shooter than all of them, but they just had something inside them that made them so much better when it really mattered.