You can get a similar jumpsuit from Arden B which retails for $59 (see another option, also for $59 here).
You'll also need some simple black pumps like this pair from Steve Madden ($79.95). Click on the photo below to purchase.
To complete Anne's simple look you'll need a cocktail ring (I found several options that would work), as well as earrings. Click on any photo below for more information.