At this moment you can create Extra field (select box type) and add required countries as variants.
We really would like to have an opportunity to suggest Country list for Teams functionality for free, but regretfully it will take a more than couple developer’s hours and we need to cover high costs of development and maintenance of the product. So the only and the immediate solution for you that I can offer is custom development. If you are interested, please submit a request with the detailed description of the required feature via HelpDesk.
Kind Regards, Irene
BearDev support team