Hi,
If your custom return url is article you can install sourcerer and do like this.
To display order amount:
{source}
<?php
if(!defined('DS'))
define('DS', DIRECTORY_SEPARATOR); if(!include_once(rtrim(JPATH_ADMINISTRATOR,DS).DS.'components'.DS.'com_hikashop'.DS.'helpers'.DS.'helper.php')) return true;
$app =JFactory::getApplication();
$order_id = $app->getUserState('com_hikashop.order_id');
$orderClass = hikashop_get('class.order');
$currencyClass = hikashop_get('class.currency');
$fullOrder = $orderClass->get($order_id);
echo $currencyClass->format(round($fullOrder->order_full_price,2));
?>
{/source}
To display order number:
{source}
<?php
if(!defined('DS'))
define('DS', DIRECTORY_SEPARATOR); if(!include_once(rtrim(JPATH_ADMINISTRATOR,DS).DS.'components'.DS.'com_hikashop'.DS.'helpers'.DS.'helper.php')) return true;
$app =JFactory::getApplication();
$order_id = $app->getUserState('com_hikashop.order_id');
$orderClass = hikashop_get('class.order');
$currencyClass = hikashop_get('class.currency');
$fullOrder = $orderClass->get($order_id);
echo $fullOrder->order_number;
?>
{/source}
Hope that helps.
Regards