Identifying a replacement patio door mortise lock

Thanks for posting. I think the 82-218 or 82-243 will be the better choice. The 82-223 has a characteristic square face, in comparison to the rounded face of the 82-218 or 82-243. This would definitely affect installation, which is why I think even with the question of the keyway being broken, the 82-218 or 82-243 look like the better match.

Ah, sorry, I should have been clearer! The reason I brought up the 82-223 is because it has the vertical keyway that you were concerned about, and immediately I honed on that issue, since it's a very common question. Apologies. To be clear, when the mortise lock breaks, the keyway spins around just like you're seeing. I'll be up front with you: we see this exact same lock dozens of times everyday. I've seen your very model, down to the 'V', countless times. I'm very confident the 82-218 is the right choice and will replace your old mortise lock. 

To answer your other question, the only difference between the 82-218 and the 82-243 is that the 82-243 is stainless steel, so its a bit more durable and should last longer. There is no operational difference, and either should work fine for you. 

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