I am new to this forum and could use some help. I have one pair of SDA SRS from 1985. I need to sell them, they are in perfect working order, but have been in house with smoking. I also have Polk surround and five small Polk speakers. I have no clue what to sell them for. I would appreciate any help. I saw some on Ebay once for 450.00 and thought they would be worth more than that. I have original sales receipt and the ad/flyer that is like one selling on Ebay.