Need help identifying these tail lights

Got these on a pick, found one on ebay but the person selling them didn't know what they had either. Stamped on the top is BLC R-M8.

 

According to this site, http://www.vsp.state.va.us/downloads/VA_Motor_Vehicle_Approved_Equipment_List/27_Stop_Lamp.pdf

it's made by General Motors and is approved for use on Virginia highways

 

Google says
http://www.ebay.com/itm/HUDSON-BUICK-OLDS-PONTIAC-CHEVY-ROD-TAIL-LIGHT-BLC-R-M8-/310316393136

http://www.ebay.ca/itm/Accessory-Ta...par-Ford-Mercury-40-46-48-49-50-/400323524564

Or try here: http://www.taillightking.com/

 

Thanks guys

 

tail light king had a pair (now sold) and he didn't know what they were

 

Thanks once again guys, highly appreciate your quick response and knowledge!