Part number is 14037664, in Group 3.675. I checked the GM Restoration Parts CD and did not find that part number listed, so your GM dealer is unlikely to have the part.
I would check the major Corvette vendors, Eckler's, ZIP, Dr Rebuild, Mid America, failing that you might start with the Corvette junk Yards. It is likely that the part is common with other GM products from around that era, so don't limit yourself to just Corvette parts sources.
The Chilton's manual uses that verbage because Chilton is using the Parts Breakout drawing from the GM Corvette Parts Manual.
Do you have a year specific GM Corvette Shop Manual? The manual for your year should have a description of this system. Chilton and Haynes are too generic for many purposes.