The most common and most likely answer to this crossword clue is the 8 letter word LONGHORN
I've seen this crossword clue in The Guardian
L
O
N
G
H
O
R
N
More clues leading to the result LONGHORN
Buddy explains!

The straight part
We know that "Kind of stock" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case kind of stock = longhorn.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 LONGHORN mean?
LONGHORN noun- A breed of beef cattle, having long horns, bred in Texas and other parts of southwest United States.