Weapons Dealer is an Underworld character that hangs out in the tavern. He is the town's Weapon Smith in disguise.
Any trader can purchase hand weapons from the Weapons Dealer, sometimes at a very low price (if the stock is large). Such a transaction is illegal, however, and may result in a fine if someone notices it.
An Alderman can freely do business with the Weapons Dealer, without the risk of being fined.