replace a mortise lock of sliding glass door to be a keyed lock

A home owner from California says:
I have a sliding glass door that has a mortise lock. It does not have key and can only be locked from inside with a lever. I want to change it to be keyed lock so that I can lock the door from outside. I saw your video of how to do it with key lock set 82-309 and patio door handle set 82-035. However, I have a screen door just outside of the sliding glass door. If I use 82-309 and 82-035, the screen door will be blocked. Apparently, I need to replace the mortise lock with a keyed one. Do you have any suggestion what parts I can use to solve my problem? Thank you
User submitted a photo of a mortise lock.
Profile picture of Tom
Tom from SWISCO responded:
Thanks for posting! There are no mortise locks specifically meant to work with keys. Looking at your picture, your mortise lock should work fine with a key cylinder. The question is, what key cylinder is right for your handle?

I think we can help. If you can, show me a picture of your outside pull. Please also let me know the maximum projection you can work with, so as to not interfere with your screen door's operation. We will try our best to find something that can work from there.
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