Some may disagree, but I'd put Hinata on the list.
She has gone out of her way to help several people despite the risks to herself.
1. Entered the Chunin exams partially to change herself, but also so she wouldn't let Kiba and Shino down.
2. Gave Naruto that healing ointment and later some more for Kiba/Akamaru
3. Unlike everyone else on the list, Hinata isn't a Kage level shinobi (ok Iruka aside), and yet she was willing to go and fight Pain who is probably an above Kage level enemy knowing she would probably die.
Anime wise she has also gone to several lengths to help others (though mainly Naruto)
1. The search for the Bikochu insect was her idea, and she fought to get the mission going
2. During the the arc with the convoy she once again takes someone on who is out of her league (he used magnetic release....name started with a J....he was a little fat), but wins (she would have died had Naruto not been there in time to save her).
Sure her actions aren't exactly on the caliber of the ones you have mentioned (well she did try to protect Naruto), but obviously she would have been the type to have easily done things like that.
EDIT: Though amongst the people you listed I said Chiyo....unlike the others she wasn't in a ultimatum like position, bit died to save a life.
