browning 20 gauge age and value

Can you tell me the age and value of a Browning 20 gauge semi-auto, serial #8Z 7540? It is made in Belgium, engraved with the words **Special Steel-20GA-Shells 2-3/4", and many tiny symbols, + another number - 8250 - on the barrel. It has other fancy engravings including Twenty in script, followed by a register mark, Browning, and a small portrait. The stock is engraved with a diamond checker pattern. Thank you.

the 8Z in your serial number indicates the year of manufacture as being 1958 which was the first year for the light weight twenty ga,,book prices for a 20ga a-5 is 450 good-750 excellent,,mabey a little higher at auction or to a browning collector depending on the condition,,dealers might offer between 350-450 for it again depending on the condition,,
bigcurt