Ok – here is a method – thanks to @Rarst for pointing me in the right direction.
Include the require file if the plugins_api function is not found:
if ( ! function_exists( 'plugins_api' ) ) {
require_once( ABSPATH . 'wp-admin/includes/plugin-install.php' );
}
Then, prepare a query to pass to plugins_api():
// set the arguments to get latest info from repository via API ##
$args = array(
'slug' => 'plugin-slug-name',
'fields' => array(
'version' => true,
)
);
/** Prepare our query */
$call_api = plugins_api( 'plugin_information', $args );
/** Check for Errors & Display the results */
if ( is_wp_error( $call_api ) ) {
$api_error = $call_api->get_error_message();
} else {
//echo $call_api; // everything ##
if ( ! empty( $call_api->version ) ) {
$version_latest = $call_api->version;
}
}
ref: http://wp.tutsplus.com/tutorials/plugins/communicating-with-the-wordpress-org-plugin-api/