Deadstock – never sold or worn – 1970s DeLISO Bronze Disco T-Straps Size 5.5N.  Heel 3in.  From the Joseph Larose warehouse.  Some minimal marking on the base of the metal toe caps.

Vintage can run 1/2 size smaller than modern sizes.  Also, while never worn, certain precautions are strongly suggested before you wear your vintage purchase:  re-glue or replace the insole, replace the lifts and replace the soles.  These actions should be easily handled by your local shoe repair.  And the minimal cost involved will improve the longevity of your vintage shoes.