Create your own Booksync widget using v3 of their API
<script type="text/javascript">
$$(function() {
var options = {
date_format : 'M dd, yy',
rental_codes : [123456]
}
$('.booksync-single').booksync_widget(options);
});
</script><script type="text/javascript">
var options = {
date_format : 'M dd, yy',
rental_codes : [75928,75929,78463,75930,75933,78461]
}
$('.booksync-many').booksync_widget(options);
</script>