Your best bet would be to check out your local vacuum cleaner shops for a good used one. Your local Kirby dealer may also have some from machines that were traded in or parted out. Not many of them around any longer. On rare occasions you may find them at the local trift stores. I got a second complete set of attachaments for my Heritage II at a local thrift store and the hose.
Sorry that some ones best answer to your question prior to this one. Was the part number that would relate to the attachament you seek. Ask the shops for a UTILITY AIR NOZZEL that is the proper name for the attachament and they will know exactly what you are asking for.
Hope you can locate one. Please let us know if you score one.