Actually, it would not be that difficult to make a basic filter, and would only require adding code to the two ez-page sidebox module files.
PHP Code:
      $box_id =  'ezpages';
      
$rows 0;
      while (!
$page_query->EOF) {
        if (
in_array($page_query->fields['pages_id'], explode(',''1,3,5,7,11'))) { //list of ez-page ids to display in this box

        //existing code

        
//in_array
        
$page_query->MoveNext();
      } 
Alternate:
PHP Code:
        if (in_array($page_query->fields['pages_id'], explode(','EZPAGES_SIDEBOX_LIST))) { //list of ez-page ids to display in this box 
and in a language file
PHP Code:
define('EZPAGES_SIDEBOX_LIST''1,3,5,7,11');
define('EZPAGES2_SIDEBOX_LIST''2,4,6,8,9,10');