I picked Toshiba drives personally. However, I know of a bunch of WD reds running for years with no issues.
I think since the nas cases aren’t insolated for sound, your going to hear them moving that head around…
Have you considered an ssd populated nas? It does cost more however :(
I got them on Amazon, the only place I could find them as well. However, I didn’t search as hard as you I think.