Hi, I just inherited four my farther-in-law a pair of perfect-working, 1972 Belle Klipsch speakers. What are they worth? Changed color scheme from dark to lighter brown in 1988 under supervision of a Mr. Klipsch upon his visit to Albuquerque, NM. Type=BKWO. Serial#s = ON817, and ON818. I can;t get photos to attach. I look forward to your replies, thanks!