
Arcadia slider door parts

The part you're referring to is the keeper. Or at least, they are normally; truth be told, I don't know what the exact style is called on your door. It looks like it's just a screw sticking out of the frame.
All's well, though, because the 82-005 comes with its own keeper that is specifically designed to work with it. The only catch is that you will need to find a way to retrofit it on your door, which could be easy or difficult depending on the frame. In my experience, the older a door is the more creative I have to get with finding out the best way to mount the keeper.
To assist in this, it comes with a bracket that allows it to mount at a 90 degree angle, if necessary. Just don't expect it to be immediately obvious where the keeper needs to install. The trick is to hold the handle up to a closed door about where it would install and note where the hook latch comes to rest. You would then install the hardware appropriately.
Thank you for the quick reply and the explanation of a "keeper". A question I now have is mounting the keeper on my door. I have attached some pics of the door. I watched the video on your site but its not clear how to mount the new keeper as there is no "side" area where I can mount the keeper. I added some pics so you can see the door. Greatly appreciate any thought you make have.
Looking at your first photo, I see a pretty significant portion of the door frame that would give you enough room to install a keeper. It's right where the handle butts up while the door is closed. Is there any reason why you can't use that area?