You can achieve this using associative arrays.
Replace
$line_of_text[] = fgetcsv($file_handle, 1024);
With
$line = fgetcsv($file_handle, 1024);
$line_of_text[$line[1]] = $line;
This way your function will return something like:
Array
(
[Andorra] => Array
(
[0] => AD
[1] => Andorra
[2] => Andorre
)
[United Arab Emirates] => Array
(
[0] => AE
[1] => United Arab Emirates
[2] => Émirats arabes unis
)
....
)
So you will be able to get the row for Anguilla using $line_of_text['Anguilla']
.