The most common and most likely answer to this crossword clue is the 4 plus 3 letter word MEMO PAD
M
E
M
O
P
A
D
More clues leading to the result MEMO PAD
Buddy explains!

The straight part
We know that "desk accessory" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case desk accessory = memo pad.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.