Nalgene make some straight sided vials that are pretty good, and have a fairly tight lid (they snap on, instead of a screw cap).

For a cheaper alternative, you can look at 35mm film canisters, the small tubes candy comes in (M&M minis, for one) the tubes that contain small amounts of OTC meds (tylenol, etc...) - there are a lot of possibilities if you keep your eyes open.

Nalgene travel vials