Since you didn't mention it in your post I'll ask you: Have to checked
HotScripts?
Sourceforge?
PHP Resource? Or searched Google for
Streaming Real Media Scripts?
If you don't find at any of these websites the odds of it being freely available and even commercially available is pretty slim. At that point you may want to consider
hiring someone to do it for you. If you do, you know you'll have a unique script and may even want to consider reslling it as others may be looking for it, too.