title: Get custom Magento attribute value for calculation
body: <p>On the Magento product page I need to construct a value of a price per piece. The product is sold as a pack of an X amount. For example I buy 1 pack of coffee cups. The pack contains 100 cups and is (tier)priced as $10. The price per piece would be $0.10 (tier price / amount per pack). For this I'm configuring the /product/view/attributes.phtml template by adding a fixed row to the table.</p>
  
  <p>What would be the best way of retrieving the custom attribute (amount_per_pack) together with the tier price of the product?</p>