If the link is always going to be the same, and you know how to get that string into a variable, this should work:
str = str.replace( "<a href='http://www.ParsTools.com/'>", '' ).replace( '</a>', '' )
Edit in response to comment
This isn't best practice, but.. Wrap the js include in a div:
<span id="whatever">
<script type="text/javascript" src="..."></script>
</span>
Then
<script type="text/javascript">
str = document.getElementById( 'whatever' ).innerHTML
str = str .... // what i said before
</script>
This solution doesn't require jQuery, which it looks like you don't want to use.