Defining a template for a page created by the module

Please suggest a solution for Drupal version 7

There is a module, and within the module, a page is defined as "module/page". For the callback function of the page, there are no issues defining a custom template through hook_theme; however, it works on the principle of a node template - displaying the content part of the page. How can I define a page-type template specifically for this page so that the template itself resides in the module folder rather than in the theme folder?

For Drupal 6, it seems that the following code works:

function mymodule_theme_registry_alter(&$theme_registry) {
  array_unshift($theme_registry['page']['theme paths'], drupal_get_path('module', 'mymodule')); 

} 

Please suggest a solution for version 7