Keep you eye on ebay, many barrels show up there. If necessary a nickle one could be de nickeled and blued. A barrel for an unpinned model will work. The barrel shank is not drilled, just a small slot cut across the threads in the correct area. Any smith qualified to install a barrel could do that to it easily.
Model 19 barrels do not show up often though. You could also use a model 13 barrel (I see those more) but, the front sight ramp and sight would have to be replaced for higher front sight to match 19s adjustable rear sight. A K frame 38 barrel from something like a model 14 or 15 would also work, but barrel shank would need some shortening and forcing cone recut as well as the barrel remarked to 357.
In any event any barrel will need adjustment when to you gun unless you get pretty lucky.