I have heard good things about these http://www.naturechest.com/roudmain.html
and these http://www.naturechest.com/harrisons.html
I get these http://www.gourmetparrot.com/exact-organic.html because it's what my pet store carries and when i first got them Levi liked them so i stuck with em. I didn't want to have to order online all the time.
Check out what ur petstore has and if you have any questions about them come here and ask if anyone uses that kind?