1. I have not yet tried Heart of Mine spam for costume pieces so take this with a grain of salt: YES, from what others have said, you can get the costume pieces. I can not 100% confirm this though. I believe the booster wing piece is a training program exclusive.
2. Well, I did maybe 10 runs and got 2 eyes... and that's it really... a friend gave me one piece and I traded a costume hair for another piece. Not sure about the current prices of Camilla pieces though. What are you looking for?
3. Yes, Camilla can drop Tina pieces.