The most common and most likely answer to this crossword clue is the 6 letter word COPECK
I've seen this crossword clue in The Times
C
O
P
E
C
K
More clues leading to the result COPECK
Buddy explains!

The straight part
We know that "bit of money" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case bit of money = copeck.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 COPECK mean?
COPECK noun- A Russian monetary unit equal to one hundredth of a ruble.
- A kopiyka: a Ukrainian monetary unit equal to one hundredth of a hryvnia.