I use these all the time. Work very well, and good value.
1/6 fl oz (5 ml) Amber Glass Bottle w/ Euro Dropper
5 ml. Glass Bottles, Amber Euro Dropper Bottles with Black Tamper Evident Caps and Orifice Reducers
The amber glass European dropper bottle with black tamper evident caps and orifice reducers could be just what you are looking for to package a range of products including essential oils and fragrances.
Tamper evident caps make it easy to determine if the product has been tampered with. The orifice reducer allows for greater control of product dispensing.