A pay website called VideoMathTeacher.com has the link below on their web site. The .zip file has the copyrighted TI83 ROM in it! I wonder if TI knows about this.
Anyways, here's the link for the file. You could collect the files elsewhere, but 1. it's all together here, and 2. let's download copyrighted material that's offered on a site that you have to pay for lol.