Vintage YSL dress black wool Jersey knit long sleeve. Size Medium LBD

Vintage YSL Yves Saint Laurent black wool Jersey knit dress with gorgeous rhinestone or crystal buttons. Circa 1980's. This is a long sleeve Cocktail dress with pockets. There is some stretch to knit. There are 3 Buttons on each sleeve as well as a row of buttons on the back. all buttons are complete with the Crystals except for one. I have the crystal so it could be added back. Note photographs. As for authenticity. I have done lots research regarding the dress. I have had no one say it is inauthentic. I have gone to 4 very high end consignment stores. 2 said it was authentic and 2 said probably. I also contacted YSL in Paris and they said they couldn't verify because they only have a history of their haute couture pieces and they suggest I go to a high end store. I also went online to see if I could find the dress and found very similar dress with the same buttons or similar (note photos) and I googled authentic ysl labels (as there are a number of different types for different eras and markets) and found it as authentic. Last photo matches the dress label minus the size. The quality of dress would also indicate it is probably authentic. No size label....will provide measurements. Similar dresses on US websites range 1400-2300. Final sale Louis Vuitton Hermes Fendi Gucci classic quite luxury saks holt renfrew elegant classic lux luxe NYE