You could do it with a bit of JS:
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
<script type="text/javascript">
$( document ).ready(function() {
$('#formElement11 label').html('I have read and agree to your <a href="http://www.readytalk.com">partner services agreement</a>');
});
</script>
Replace "formElement11" with the actual ID of your checkbox element's containing div.