Magento - Use an Alternate "price.phtml"

This can be done in a layout xml file. Create a local.xml file, put it in app/frontend/YOURTHEME/layout:

#local.xml

<?xml version="1.0" encodeing="UTF-8"?>
<layout>
   <!-- Override price template on product view page -->
   <PRODUCT_TYPE_simple>
       <reference name="product.info.simple">
           <action method="setTemplate">
               <template>catalog/product/price_product_page.phtml</template>
           </action>
       </reference>
   </PRODUCT_TYPE_simple>
</layout>

Create a copy of catalog/product/price.phtml and put it in YOURTHEME/template/catalog/product/price_product_page.phtml