The most common and most likely answer to this crossword clue is the 4 plus 1 plus 3 plus 4 letter word LAND O THE LEAL
I've seen this crossword clue in The Guardian
L
A
N
D
O
T
H
E
L
E
A
L
Buddy explains!
The straight part
We know that "Scottish heaven" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case scottish heaven = land o the leal.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.