Update { should have benchmarked properly, apparently.. rest of this post largely invalidated by runrig's reply. }

Abigail-II's proposition of grep -l does not fit your specs as it will still scan all files, but your Perl can be simplified.

perl -e '
    $site = shift;
    for $f (@ARGV) {
        local @ARGV = $f;
        /^Customer Code/ && last while <>;
        / \Q$site\E$/ && (print("$f\n"), last);
    }
' $code *

[download]
But why all that? A shortcircuiting sed script to find a customer's code: sed 's/^Customer Code[^ ] //; t done; d; : done; q;' FILE Wrap some sh around it and it does the job: 
for ALIAS in * ; do
    [ "`sed 's/^Customer Code[^ ]* //; t done; d; : done; q' "$ALIAS"`
+" = "$code" ] && break
done
echo "$ALIAS"

[download]
(Wrote this in bash, not sure if it works 1:1 in Korn, but it should be easy to port anyway.)

Update: Btw: when you're passing {print $?} to awk, it's a sign you really wanted to use cut - in your case, that would be cut -d: -f1

Makeshifts last the longest.

In reply to Re^2: Code Efficiency: Trial and Error? by Aristotle
in thread Code Efficiency: Trial and Error? by Tanalis

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