the correct code to validate the county if state province is NY would be:
<?php echo(((isset($_POST['shipping_state_province']) && $_POST['shipping_state_province'] == "NY")?$_POST['county']:"NA")); ?>
the correct code for NY OR PA would be:
<?php echo(((isset($_POST['shipping_state_province']) && ($_POST['shipping_state_province'] == "NY" || $_POST['shipping_state_province'] == "PA"))?$_POST['county']:"NA")); ?>