DF,
Do they still make those 29” versions?
I don't think so.
It's hard to get a straight answer about that gun and how it came to be.
One version says they were built for a jobber who ended up not taking them, so CZ put them on the open market. A limited run for sure.
I got mine used at a gun show. It already had been painted red. I didn't like the red, painted it brown with Brownell's Alumahyde II, which is a really tough paint. Here it is, red and before the Timney. Careful inspection shows a slightly different trigger profile, CZ vs. Timney.
DF