The most common and most likely answer to this crossword clue is the 10 letter word BACKPACKER
I've seen this crossword clue in Independent
B
A
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K
P
A
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Buddy explains!

The straight part
We know that "Walker perhaps" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case walker perhaps = backpacker.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 BACKPACKER mean?
BACKPACKER noun- A traveler whose luggage consists of a backpack; especially, such a traveler who uses hostels, public transport, and other inexpensive services.