I ended up buying a Tanfoglio extended magazine catch/release from Ben Stoeger for just over $20. Since the CM9 Gen2's frame is thicker in that area I had to do a little trimming to make it fit but it's pretty strait forward. I didn't even have to remove the trigger assembly. I just removed the trigger pin, trigger bar spring assembly and mag catch/release. If you leave the hammer in double action the trigger bar will be far enough forward to remove the trigger bar spring assembly.
I went from this factory mag catch/release to...
This Tanfoglio extended mag catch/release from Ben Stoger. They seemed to have the best in-stock price I could find at the time. The locking tang on the extended catch is a little wider, or thicker depending on how you look at it I guess, but seems to lock into the mags just fine.
With trimming this is the final outcome. The factory mag catch sat flush with the frame so this one is much easier to reach and operate. Factory mags still fit and lock in as well as MecGar 16/17/&19 rounders. They all still lock the slide back too. I haven't been to the range yet to make sure the mags don't fall out during live fire but will report back when I do.