Inside lock part
A quick learner from USA says:
August 22, 2016
I removed my sliding door handles and inside lock part to take to home depot as requested. While I was taking it out something fell out between the door. The handle set seems to be your Swisco product code 82_079 but I cannot tell what the lock part number is. Please help hardware stores don't seen to carry this.
Tom from SWISCO responded:
August 23, 2016
Sorry to hear about the trouble! If your mortise lock fell into the door, there's probably only one culprit. See our 82-218. This lock is the only mortise lock that comes to mind where such a thing is a risk. Does this look familiar? Carefully look over our measurements to ensure that it matches the holes in your door where the old lock went.
I also recommend watching the video below. This will help you avoid the same accident happening in the future.