unused  -- 1a. on 1 sio, variety surcharge inverted, fine mint. Siriwong 20/2b, B30,000. Photo
unused -- 1a. on 1 sio, variety surcharge inverted, fine mint. Siriwong 20/2b, B30,000. Photo

Details
unused -- 1a. on 1 sio, variety surcharge inverted, fine mint. Siriwong 20/2b, B30,000. Photo