Two point mortise lock on sliding patio door. 3-5/8 hole centers

Wow, this is a weird mortise lock. I've never seen anything like it before. It looks like someone liked the idea of the 82-218, which is a very common part, but decided to change the design a little bit for whatever reason. Maybe they were trying to skirt around a patent.

I can tell you that we won't be able to supply you with an exact match for your original part, but I do wonder if you could just use our 82-218. Look over our dimensions for this part and let me know what you think. You'd also probably need a new 89-021D keeper.