In terms of what I can find for the outfits:
Hariette Battlewear [Ou] (?) - I'm not too certain on this but the sleeves seem to look close.
Soaring Silks: Snow [Ba] - You can look up color variations if you wanted something else.
Wings of Darkness B - I'm not certain if these can be colored like that person has it in their video.
I do not know if the Halo was available as part of a Fresh Finds or a bonus for participating in an older AC Scratch as the catalogue I was looking through does not list them (which means they likely are not normally obtainable).
Fashion Database for future reference
If the Player Shop search does not work for you in coming up with the auto-complete results you must manually enter the full name (copy/paste works too) and then search the item without the auto-complete by simply searching at the bottom-right of the menu. You will not see items you have not "seen" in-game become cached until you see them either on another player or seeing them in the menus.