How to prevent Purchasing from ordering an item

Is there a way, other than stocking type, to prevent Purchasing from including an item on a purchase order?

Example:  Item A is currently out of stock, but there is a shipment en route, so we want the material to backorder on sales orders.  Once this shipment is received, the item should never be ordered again.  After 12-31-13, it will no longer be legal to sell this product in the US.

If we set the item to stocking type U or O, the item will not backorder on sales orders.

Any suggestions would be appreciated.

Maggie