Designed/shortened for the flying garment bag & notched to lock in place - this came with my Andiamo garment bag, semi-retired now - used extensively in the 80's and eary 90's for domestic & TPAC segments (came with 2) and have 2 spare ones from an American Tourister. Paired with a carry-on duffle bag, only gate-checked it a few times as FA would often find a place to stash it away (DC10's and even 767's have closets for the bags, I seemed to recall

) if OHB's were filled up if boarding late from a tight connection.
Unlikely to find them at Macy's - but Samsonite/A.T. discount stores (i.e. Tanger Outlets) would be a good place to call & ask if they have these as replacement parts in their store inventory.