Filter for unassigned Cases

Hi good people!

I´m setting up another inbound email handler that will create sales related Cases.

I need to be able to identify those sales related Cases from other brake-fix Cases so I can make a filter for those employee´s attending only to those sales related Cases.

I was going to filter on the unassigned until I remembered that we only have two options there:

I don´t seem to be able to set any fields in the inbound email handlers :/  Any ideas how I could solve this use case?

Thanks in advance,

KGM