need to know its worth and it doesnt have a serial or model # ion the washburn b

http://www.guitar-museum.com/guitar-101209-1985-86-mirage-pro-SBF24-12-DL
 this doesnt have a serial number nor model number  on the wood block in the sound hole ,it does say George Washburn -Mirage pro ,I bought this new in new york in 1985
 kind of l...