[Alawishes]

I am new to owning guinea pigs. My piggy doesn't really like oranges and she has food that has vit c, but I'm paranoid that she's not getting enough and then I'm afraid of over feeding it....so How much is too much and what other foods have a lot of vit c? I know you probably get asked this ALL the time, but pls be patient w/ me. I feed her variuos timothy hays (block form, hay, hay/flwr mix/ hay/veggie mix, etc), collard greens, carrots, parsley, oranges.
She love vitc yogart treats, but I do not want to feed her a lot of dairy, piggy muffins (a treat I got at the petstore), these little hay treats that look like mini wheats......I think that's it.....what other foods are high in vit C?