Making your own Cola - Finding the herbal oils?!

Making your own Cola - Finding the herbal oils?

As a chemistry experiment, our class wants to make their own cola. We are having problems locating the herbal oils needed. We can find essential oils, but due to the distillation process those can't be directly ingested? (at least thats what the labels say)

The local supermarkets don't have everything we need. Is there a reputable dealer we can order from online?

Specifically we are looking for California cold pressed lemon oil, neroli, and distilled lime oil.

Thanks for any suggestions!