Dashboard filter from manual source

Hi

I'm trying to add a simple dashboard filter to our support desk stats that will filter several reports on the dashboard.
The filter will (depending on a single selection) put the associated query into the filter. But the selection for the filter button doesn't exist in a table.
The filter button should simply select Global, US, UK or Asia

Select Query
Global "US::New York" OR "US::Texas" OR "UK::London" OR "UK::Manchester" OR "Asia::Shanghai" OR "Asia::Singapore"
US "US::New York" OR "US::Texas"
UK "UK::London" OR "UK::Manchester"
Asia "Asia::Shanghai" OR "Asia::Singapore"

My problem is that none of the queries currently exist in my data source that I am connected to, so I cannot simply reference an existing table or query.
I guess I need some sort of "local" or "temp" table that I can keep these mappings in as I cannot create a custom table in our datasource?

Any pointers on tackling this would save me hours of creating multiple dashboards for each query.

Thanks

Try to create an empty question and use that one as source?