I found an Amazon jumpsuit that is so similar to the Spanx Air Essentials Jumpsuit. The Amazon option is currently 20% off, under $29 when you use promo code 20KQ1P9Q. Promo expires 8/07 at midnight PST (but can end early or sell out).
I am wearing a size small and find it true to size. I am 5 feet tall wearing 3.5 heels, and its a smidge long (bot so cute that I will make it work anyways). Click below to shop.
I have linked the Spanx Jumpsuit below, if you would like to check it out as well. It is currently $148.