replacement key cylinder

A home owner from san antonio tx 78248 says:
My home has a Newcastle XT sliding patio door that was installed in 2002. The tailpiece on the key cylinder is broken off. I received no owner's manual or instructions of any kind when the home was built, and there are no names, numbers, or markings of any kind on the existing (original) key cylinder. What do I need to use to replace the defective one?
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Tom from SWISCO responded:
Could I see a few pictures of your existing handle? This will help us find a possible replacement for your key cylinder.
A home owner from san antonio tx 78248 says:
Thanks for the quick response, Tom. I'm not much of a photographer, but maybe these will work.

The lock is a Schlage.
The cylinder diameter is 9/16"; its total length (including the nut and the keyhole piece on the ends) is 1-1/4". Just the cylinder itself is 7/8" long.

The fin on the cylinder is 3/16" wide, 7/16" high and 15/16" long. There's an access slot along the upper edge for rekeying the lock.

The tailpiece is broken off at its base at a sharp angle, leaving a point about 3/8" long (from the base).
User submitted photos of patio door hardware.
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Tom from SWISCO responded:
Great, these pictures are just what we needed to see. I recommend starting with our 82-310 . Check it out and let me know if you think this could be a possible replacement.
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