User selected global filter for country

I am trying to build a scenario where I have a km repository like the following

Australia

- Support docs

- Product Brochures

USA

- Support docs

- Product Brochures

Then I want to build a KM navigation iView that allows the user to select a global "filter" of their country... An Australian user would select Australia (a pre defined property per the global property service) and then this would be used to drive the content shown in the iView.

I should be able to do this via permissions but I would rather have the user select the area of interest as they may be authorised to see both.

Does anyone have any ideas on how this could be done?

Thanks in advance

Bernard