It sounds like either the choke cable or the choke plunger (starter enrichment valve) is stuck? Try squirting generous doses of penetrating oil in the cable while you are operating the lever back and forth (don't force it too hard and break it) and maybe you'll get lucky. You can pressure lube that cable too if you have one. If it is frozen somewhere down near the carb you may have to take the plastics and tank off to grab hold of it and bend it every couple inches or so to break rust loose inside the cable sheath, while you work the lever. Once you get it free, you can use it until your new cable arrives.
You can find a copy of the service manual HERE. Welcome to the forums!
You can find a copy of the service manual HERE. Welcome to the forums!