This is the outfit worn by Harry in the final 2 episodes of Blunt Talk when he goes to the Surrealist Ball. The outfit consists of the following items.
Black velvet dress with studded pearl collar and cuffs with a gold broach in the centre. The dress has no tags and appears to be custom made for the TV series.
Jewelry - a pair of clip-on earings made by the brand Sophia. An ivory opal ring with set stones around the opal.
Stiff black purse, with an aligator pattern.
Black Clarks heeled shoes.