confused about coolant pipe

[stouchton]

I need to replace the coolant pipe - welded bung has a leak when it gets hot and the replacement pipes seem cheaper than the time spent to reweld and repaint. My current pipe is not an original.

Should the pipe be painted black, or should it be unpainted stainless steel?

I got confused when the Snyder's catalog called out an unpainted stainless pipe for the "show cars". I have only seen them painted black.