I do that in customer.itpl.php for the delivery country :
<?php
$delivery_country = uc_get_country_data(array('country_id' => $order->delivery_country));
echo $delivery_country[0] ['country_name'];
?>and for the billing country :
<?php
$billing_country = uc_get_country_data(array('country_id' => $order->billing_country));
echo $billing_country[0] ['country_name'];
?>It seems working...