Judging from the jersey knit material, the use of metal hook and eye closures, and the label, I'd guess this was from the 1960's or so. The label is from the Brooks Costume Company in New York City, and stapled inside was a paper stating "ST. JAMES". (St. James theater?, a play about St. James?)
The gold-colored braid is still very bright and very heavy. Unfortunately, about half of the applied 'pearls' are missing, leaving small holes where they were once attached, and the bottom edge of both sleeves are seriously tattered. It would be nice to know when and why it was first worn, or who wore it.
No, I didn't buy it, which may have been a mistake. After a quick internet search, it turns out that Brooks did supply costumes for the big play and film productions, and was bought out in 1981 by rival company Eaves, afterwards to be known as Eaves-Brooks.
I set it on the side to take this picture (without the flash, not to cause attention.) It was one of those things you can't describe. Ya' just gotta see it.