Have you seen this great resource by the North Carolina State Historic Preservation Office?

Downtown Sparta, North Carolina and its historic landmarks, on the NC State Historic Preservation Office map.

Just go to the site, click the disclaimer at the bottom of the screen and you can see the location and status of many (many!) historic sites around Alleghany and beyond.

https://nc.maps.arcgis.com/apps/webappviewer/index.html?id=79ea671ebdcc45639f0860257d5f5ed7&center=-9030320,4370440,102100&scale=4514