If it's for Halloween, I guess Wish won't make it in terms of deadline.
So depending on your deadline, why not a DIY cape ?
It's an easy shape to sew, whether you're a beginner or not, and even without a sewing machine.
If you go to a shop like Tissus Gras (rue de Coutance near Manor) or to Bernina (Praille commercial center) you'll find catalogues of patterns (but may takes times to get ordered...), and get an idea of what's possible ?
I used to collect some fancy outfits.
- an extra extra long dress, kind of medieval or gothic style, with beautiful bat sleeves, size 38-42 approx. It's currently red, with a lining in white/pinkish "dentelle anglaise", but could be dyed in black, I guess. Could be used as a dress or cut open to look like a coat (for sale, maybe ...).
- a gothic extra extra long black coat size 38 approx for someone quite tall (for sale, but original price was very high, so ....)
- a cape, black velvet with a pink silk (?) lining, waist lenght unfortunatley, but with an intersting thick collar (for sale)
- a beautiful cape, exactly the style you're looking for (ankle lenght, black velvet with a hood), but this one I keep it preciously, but could be used to copy a home-made pattern to sew.
Don't have pictures because everything is stored in boxes in the attic, but could make some if needed.
Most of these, I've bought them at the Plainpalais flea market, around this time of the year before Escalade.