Looks a lot like a Shlage/Emtek or similar.
Same keyway just different appearance or slightly different sizes
There are a couple of ways to do this.
1. Measure all dimensions carefully and compare to drawings of potential replacements
2. Buy one of each of any lock that looks the same. Then try each one out.
3. Post on a locksmith forum.
4 try to find hardware
to replace entire mechanism not just lock.
5, same as 1 or 2 but try to find a lock cylinder (the part that the key fits in held in with the two phillips screws)
in the center of the lock that will fit into this one
6. Find a good locksmith in the USA and fed ex them to him.
I use Tony's in San Clemente California
. Great people.