Hi, The initials are DVR in Cyrillic, standing for Dalne-Vostochnaya Respublika, the Far Eastern Republic.
Appears to be Far Eastern Republic #8 with a price in my 2010 Scott Classic of $2 used or mint. By the way, my Russia BOB is missing that stamp!!
Harvey! I will check and see if I have a duplicate, but I don't remember seeing one. If so, I will msg. you.