I wonder if this is one of the instances where the item is missing from either BKICMSTR.B OR MTICMSTR.B (I forget which one).  I assume this part has been in existence for a while.

If there is a record in BKICMSTR the part will come up in IN-B where you can just tab through and save it to restore it in MTICMSTR. If it is in MTICMSTR and not in BKICMSTR then IN-B will say it does not exist and ask you if you want to create it. Recreating it will restore everything else (locations, history, allocations, etc.)