I have a 5" 5-screw pre-27 with a damaged plain rear sight blade and I need the replacement blade and hardware. Knowledgeable folks here advised me that asking here instead of going to Midway or Brownells could net me higher-quality parts compared to the new stuff (along with them being period-correct parts, such as the correct flatter-faced windage screw)
So there you have it, I need a period-correct rear sight blade and hardware, and would prefer it to a new one.