Archaeik |
Sandman Bard archetype gets it
numerous PrC offer Sneak Attack
Assassin
Arcane Trickster
Master Spy
Pain Taster (well it's similar to SA)
I'm sure there's more
edit: as a note, you need to be mindful combining classes w/ SA as some say that class levels stack to determine SA(like Vivisectionist) rather than just saying SA stacks(like Assassin)