My son in law has an older 2.5-7 AO Shepherd scope. It came on a Savage Tactical 308 he bought and has since sold the rifle. Whoever had the rifle & scope before him put a lot of ring scratches on the scope. After he sold the 308, he put it on a heavy barrel .223. But other than the scratches, it's in good shape and works as advertised. He'd like to sell it to buy a 4x12 or a 4x16 scope for the .223. Does anyone has a guesstimate of what it might be worth?