Seem busy making attire for the period piece (6)
I believe the answer is:
bustle
'piece' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps there's a link between them I don't understand?
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for bustle that I've seen before include "Victorian fashion" , "Hustle and fuss" , "Scurry - frame worn under skirt" , "A show of hurrying, or old skirt back padding" , "A subtle sort of commotion" .)