Which mortise do I need?

Your door is not compatible with any mortise that's used with the 82-087,  or any mortise at all for that matter. Your old handle looks more like the 82-002 Your door is designed such that you can't really use anything else but what you have now. Unless you buy a new door, this is what you're stuck with. 

The hardware you bought will not work for you. I recommend returning it for a refund when you receive it; see our return policy here.