Outside of asking here, is there any place that one can go for replacement caps?
Cap as in top for atomizer or for splash bottle top?
My suggestion, if you want the legitimate cap, is to go to the company itself and see if you can get one. I've never heard of a place that sells them. Otherwise try a department store. They usually keep their samples without the caps on, so if you have a more mainstream bottle then you may be able to get one of the caps they don't use.
Worse comes to worst you can decant it into your own bottles, and there are plenty of places to get them.
EnvYuS My Wardrobe