The most common and most likely answer to this crossword clue is the 10 letter word OBTAINABLE
I've seen this crossword clue in The Daily Telegraph
O
B
T
A
I
N
A
B
L
E
More clues leading to the result OBTAINABLE
Buddy explains!

The straight part
We know that "to be had" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case to be had = obtainable.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 OBTAINABLE mean?
OBTAINABLE adjective- Able to be obtained.