The Geographic unit is no more available in ACS (Deprecated and Removed Features in Campaign Standard) , so you can't use this here. However. You can achieve this by assigning the Org Unit for a specific country to the profile. Hope you have created various Org unit for your different countries? When you upload your profiles using Workflow assign the Org unit to the profiles and all the users assigned to that Org Unit will only see these profiles. If you are getting the profiles via rest API, you can reassign the Org unit by running a workflow that can be scheduled to run frequently.