Molly,
Thanks for the question! Those mirrors were ordered by my clients several years ago, but they were about 36x36" square. Here are a few links I found of similar mirrors that may set you on the path to finding what you like!
https://www.wayfair.com/Rosalind-Wheeler-Tuscan-Square-Wall-Mirror-RSWH6355.html
https://www.wayfair.com/Howard-Elliott-Millennium-Mirror-RD1138.html
http://www.potterybarn.com/products/5447599/?catalogId=56&sku=5447599&bnrid=3380801&cm_ven=Google_PLA&cm_cat=Shopping&cm_pla=Feed&cm_ite=Google%20Base-5447599&kwid=productads-adid%5E154026493659-device%5Ec-plaid%5E100701578731-sku%5E5447599-adType%5EPLA&gclid=CIzVmq6h6NICFcW2wAod-jsB_Q
Best of luck with your search!
Hallie Veith
328 Design Group
303.350.9155
328 Design Group