A 16, 12 or 10 dram vial will be quite easier to fit vs a 20 dram. You could go to a local pharmacy that does offer smaller and request to buy a few. Many people use them for storage of small parts for hobby collection btw and then apply the label you're given from CVS to those smaller bottles and reserve them solely for travel purposes (updating if your dosage changes). I just looked at my CVS 20 dram with label and it would fit on the 16 fine and with just a little overlap on the 10 or 12. In the industry, if the label doesn't fit to display all info you can fold over the part with information about side effects/pill description so it sticks to itself creating a tab that with overlap with the rest of the label but not block it from being read.