I think Im getting there I know:
$where = str_replace("meta_key = 'cobertura_%", "meta_key LIKE 'cobertura_%", $where);
I have
'key' => 'cobertura_%_pais',
'compare' => '=',
'value' => '5443',
Just need the value for value => ” because in te DB the value is
“a:1:{i:0;s:4:”5443″;}”