I just picked up a TI-NSpire for nearly nothing. It's missing the battery door for the rechargeable battery (which is also missing). I can pick up the battery easily enough but I can't find the door anywhere! See the door (and it's screws ... which of course I don't have either) in the pic below. Halp! edit: I noticed the picture is of a CAS ... I have a plain jane nspire. Another pic shown below seems to show that the battery door is the same. Amazon prime has the battery @ $11.01.