Yep,
with pistol calibers, the longer barrel may not give you much. I'd say up to 20" (or 21" like the old contender barrels).
But 16-18" would be just fine too.
Why are you seeking a 44 MAG specifically? how about a 357 Maximum (or is that too long of a case for Indiana?)? The 357 Max will shoot flatter, but it's really not the end of the world for either of these calibers at their effective ranges.
JW