Anything that will fit a 2" Smith J frame should work. If you want to be real cautious, specify a 357 Smith (as I suspect the frame is slightly longer for the longer cartridge) but I don't think it will matter.
Most holster makers will make something (or lots of somethings) for a J frame. I use a cheap Uncle Mikes pocket holster but I've also heard great things about Mikas Holsters. I heard about them after I got my UM. Here's the link: