poaro Hi. Sorry for delay. I've unsubscribed from this thread by accident.
Are those prices in a different extra fields? If yes than You need to use other names. And please remember that there is a small issue in documentation, where it says to call extra field by alternative title, it actually means a regular title, for example: {{Title of extra field}} with spaces and capital letters.
If You will require more help with it please tell me how would You like it, attach an access to joomla panel and copy the current "own article format" You are using in NSP.