How much should I sell a belt buckle for ?

The belt buckle is an LRG belt buckle that was worth $ 25 when I bought it know its old and I want to sell it.How much should I sell a belt buckle for ?maybe in a $15-$20 range... maybe as low as $10 depending on how old it isHow much should I sell a belt buckle for ?$500.00 and say it has sedimental value behind it to trick all the neighborhood idiots.