I did some work on it, the sie file thingy, still lots to go though.
Turning the swedish parts of utf-8 into PC8 (cp437) with javascript:
<script>
retval='"ÅÄÖåäö" ';
document.write('I want ' + retval + ' encoded in pc8 = ');
retval = retval.replace(/Å/g, '').replace(/Ä/g,'Ž').replace(/Ö/g, '™').replace(/å/g,'†').replace(/ä/g,'„').replace(/ö/g,'”');
document.write(retval + '');
</script>