BR means birch raw ,
one of my pairs was a BR , the other was a decorator model that was redone by Klipsch into a grill model .
Seems that they over made the Deco's & they didn't sell well , Klipsch took some back & converted them into Grill models
The decorator model was a fully veneered cab that was sans grill & have a veneer front with exposed horns & woofer , they were quite stunning looking .They are Now very rare
My BR set was that way from the start , I was only 20 years old when I got them & it was $500.oo bucks cheaper to buy them un-finished .
me being single & moving many times for many years for so long I never did finish them .