Between 5000 and 10000 depending on the condition and whether or not you have all the manuals, lesson books, the bench and earphones. They are usually posted for sale for 7500 or best offer.
It's not worth much if someone was to offer you $100 you should take it. Organs aren't worth much unless they are made by Hammond. These old organs are big, not portable, sound bad. The casio that...