protected function _getStoreId()
    {
        $storeEnv = Mage::app()->getStore();
        if ($storeEnv->isAdmin()) {
            /** @var Mage_Adminhtml_Model_Session_Quote */
            $quoteSession = $this->_orderHelper->getAdminQuoteSessionModel();
            // when in the admin, the store id the order is actually being created
            // for should be used instead of the admin store id - should be
            // available in the session
            $storeEnv = $quoteSession->getStore();
        }
        return $storeEnv->getId();
    }