The most common and most likely answer to this crossword clue is the 8 letter word EQUIPAGE
I've seen this crossword clue in Financial Times
E
Q
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More clues leading to the result EQUIPAGE
Buddy explains!

The straight part
We know that "Ceremonial stuff" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case ceremonial stuff = equipage.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does EQUIPAGE mean?
EQUIPAGE noun- Equipment or supplies, especially military ones.
- Military dress; uniform, armour etc.
- A type of horse-drawn carriage.
- The carriage together with attendants; a retinue.
- To furnish with an equipage.