How to get the Name and e-mail addres in plugin?

function onAfterOrderUpdate(&$order,&$send_email){
	if(!empty($order->order_id)){
		if($order->order_status == 'confirmed'){ 
			$userClass = hikashop_get('class.user');
			$user = $userClass->get($order->order_user_id);
			$username = $user->username;
			$email = $user->email;

<?php
/**
 * @package	HikaShop for Joomla!
 * @version	2.1.3
 * @author	hikashop.com
 * @copyright	(C) 2010-2013 HIKARI SOFTWARE. All rights reserved.
 * @license	GNU/GPLv3 http://www.gnu.org/licenses/gpl-3.0.html
 */
defined('_JEXEC') or die('Restricted access');
?><?php
class plgHikashopInterspire extends JPlugin
{
	function plgHikashopInterspire(&$subject, $config){
		parent::__construct($subject, $config);
		if(!isset($this->params)){
			$plugin = JPluginHelper::getPlugin('hikashop', 'history');
			if(version_compare(JVERSION,'2.5','<')){
				jimport('joomla.html.parameter');
				$this->params = new JParameter($plugin->params);
			} else {
				$this->params = new JRegistry($plugin->params);
			}
		}
	}

	function onAfterOrderCreate(&$order,&$send_email){
		return $this->onAfterOrderUpdate($order,$send_email);
	}

	function onAfterOrderUpdate(&$order,&$send_email){
		if(!empty($order->order_id)){
			if($order->order_status == 'confirmed'){ 
				$userClass = hikashop_get('class.user');
				$user = $userClass->get($order->order_user_id);
				$name = $user->username;
				$mail = $user->email;
				
				// Testing
				$results = print_r($userClass, true);

				// Test e-mail
				$to      = 'mailservice@****.nl';
				$subject = 'A user has been added to the FollowUp list';
				$headers = 'From: info@****.nl' . "\r\n" .
						   'Reply-To: info@****.nl' . "\r\n" .
						   'X-Mailer: PHP/' . phpversion();
						   
				$message .= "Results Array:  $results \r\n" ;
				$message .= "Name:  $name \r\n" ;
				$message .= "Email: $mail" ;

				mail($to, $subject, $message, $headers);
			}

		}
		return true;
	}
}

$results = print_r($user, true);