Sambonator,
I am pretty sure it was a 29. It could have been a 24 or 25 but I know Maganaport made them from 29's and they would be most common.
The 3" (little longer) S&W N frame is becoming very popular. I also have one in 45 ACP and want one of the new 3" 610's in 10mm. 3" 44 mags are easy to find now, S&W makes a few differnet versions.
The 2" verson required shortening the ejector rod and meant you couldn't fully eject the cases, you had to rely on some gravity. The 3" version has a full length rod that gives full ejection. For that reason, the 2" custom guns are few and far between. After S&W started offering 3" 44's from the factory, people stopped offering chop jobs.
NJW