Your Paypal account will have all the information you need about an item that has been dropped by eBay, although not all the information you may want.
This includes tracking information, title (but not description and picture) , and the buyer's own email.
Do you keep your own record of your item descriptions and your pictures? I have a couple of folders on my desktop with those, which is about as hi-tech as I get.
I guess it makes some sense if the dispute is being done through Paypal that the information is there on Paypal, since eBay is no longer involved.
I think of chargebacks as being related to credit cards rather than eBay/PP. Is that what you mean?