Change Post Template based on post meta?

Try following code it will work with if statement as well.

define( 'MY_PLUGIN_PATH', plugin_dir_path( __FILE__ ) );

function catch_plugin_template( $template ) {

    if( is_page_template('page_template.php') ){

        $template = MY_PLUGIN_PATH . '/page_template.php';

    } 

    return $template;   
} 
add_filter('template_include', 'catch_plugin_template');