Yes you can still get these, but they are typically only available used at this point due to the age of the system which has been discontinued for quite some time now.
You may purchase a used one here: http://amzn.to/2gm82RO
When you get it, you'll have to "register" it to your existing system. To do so, press Menu#130 on the new handset, then press and hold the locator/find hs button on the main base for 5 seconds, then OK on the handset, and it will beep to confirm it is working.
If you'd prefer, it may actually make more sense to start over, you can get a brand new bundle system with several handsets for not much more than another single handset. I can recommend options for that too, if you'd like.
If you have any other questions, just let me know. Otherwise, please take a moment to rate my service as this is the only way I am credited for my time. Hopefully I have earned 5 Stars but if not please let me know what I can do to ensure you are satisfied. I also invite you to contact me directly with any future support needs at http://bit.ly/1QwLxGh and ask for Nathan.
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