Bust: 32 in to 40 in, since its stretchable
Not sure about autheticity
Some signs of wear such as lint balls, but not too visible and can be easily removed with lint ball remover

Disclaimer: Please check pictures of defects carefully, if applicable. Most items might not have defects but is used. So signs of wear like lints and thread pull etc *could be there* (not necessarily), but negligible.