Perishable or outdating items are known to require special management attention due to their high obsolescence or perishability costs. Typical examples of items with limited shelf-life include fresh produce, drugs, chemicals and films (Nahmias (1989)). Our study of product selection policies for perishable items has been motivated by related problems arising in the management of special consumable materials and assembly components in the aerospace industry. These highly specialized items include, for example, structural adhesives, dry film lubricants, fuel cell sealers, batteries or gas energized launchers and ejectors. Compliance with standard age control requirements can limit the shelf life of these items to anywhere between nine months to two or three years. Long term supply contracts from multiple sources are established to assure the desired availability and quality levels. Interleaved deliveries from multiple sources, variability in shipment times, sporadic rejection by the receiving quality inspection tests - altogether give rise to random supply times. The typical demand pattern for many of these items is also random. In such systems, where the replenishment rates and demand rates are random, the determination of the distribution of the stock level is difficult because such evaluation must include the stock level at every age layer.