+1 on El Paso Saddlery. They use the best materials with excellent craftsmanship. I'm thinking seriously of getting a western holster for a 6" 629, or possibly the style they made for General Patton. I have no illusions about concealing that hog leg.
You won't be very happy with a generic holster. They don't fit well, and don't carry well on a belt - generally loose and floppy. You spend nearly as much as for a custom holster. The only advantage is availability without a long wait.
Besides El Paso Saddlery, look at Ryan Grizzle's ware, also high grade leather and craftsmanship, with an emphasis on long service and concealability. A 5" barrel is a little long for IWB, but a Sparks VM2 would be the best choice. I have two VM2s for 3" revolvers, L and N frame, which work smoothly and are comfortable. For 4" or so, a pancake holster is a good option. Avoid a high-ride. You have to be a contortionist to draw a long-barreled revolver from under your armpit.