Survivor Benefit Plan Insurable Interest Fairness Act - Amends Federal provisions concerning the Survivor Benefit Plan for military personnel and their dependents to provide that, if the reason for discontinuance in the Plan is the death of the beneficiary, the Plan participant may designate a new beneficiary, who must be a natural person with an insurable interest in the participant. Requires such designation within 180 days after the death of the previous beneficiary.