Same Problem, Best Solution!
After some research I purchased a Trimark Latch repair kit and I'm pleased with a complete and permanent fix for $49.
The kit includes a steel replacement piece, wrenches you'll need for the fix and a new spring, in case you lose yours like I did. This allows you to use your existing keys and it installs with no "modifications" needed which may not be the case if you just buy a brand new Trimark Lock.
To be fair, I have read that the new Trimark locks use a steel latch piece rather than the crummy pot metal ones that break.
Here are links to the Latch Fix website and the video showing how easy the fix is to do.
https://www.latchfix.com
https://www.youtube.com/watch?v=efW38pxwzZI
Cheers,
-Grouchy