Bill,
Have you looked at the discontinued parts functionality in the MRP4 view of the material master? We have not implemented this ourselves (we just researched it for the same reason as you) so I don't know exactly how it behaves but reading up on the topic, this may be exactly what you're looking for. Link to more information.
The concept maybe relevant for sub components than the actual finished goods/ items sold to customer but the concept should work in either case.
Krishna