no that wont work, because in Maya 7, the command polyHelix is a pre-scripted primitive. So if you try that in Maya 6.5 or 6, it will just give you a syntax error. And as for the other signs after the polyHelix command, they are not needed; they just tell the dimensions of the helix.
As for a script, why don't you just go to google.com and search for helix script in maya 6.5? Im sure you will find something.
hope that helps.