Need Keyed Patio Door Handle

Thanks for writing in. This handle set looks like our 82-035. The outside pull of this handle set can be adapted to accommodate a key lock & housing like our 82-315. The video below illustrates this process. 

However, I'm a little concerned about your patio door. It looks to me like it might have been modified to incorporate an internal mortise lock. I'd remove the handle set just to make sure you can follow the procedure shown in the video below; i.e. that the outside of your door has holes that allows a key lock to access the keyway of the mortise lock. Let me know if you have any problems. 

If you don't have a hole to accommodate a key lock, then your only option is to make one. You'd have to drill it to size and use a rat tail file to make it nice and even. If you aren't comfortable making that kind of alteration to the door, you may want a local professional to come out and do it for you.

Nope! Everything looks like it's good to go to me. You shouldn't have to drill anything.