Leather.
OWB: Roy Baker Pancake. A 4" N Frame carries comfortably and close all day and/or night.
IWB: Galco Cozy Partner. The only way you know a J-frame is there is if you reach back and touch it.
Pocket: Owned and used a Desantis Superfly for a Remington RM380 and a Nemesis for a Bersa Thunder. Both worked, but still didn't like them as well as an Uncle George pocket for the Remington or a Galco horsehide for the 642.