Frank Decaro looks like a kid as he takes out the Swedish foghorn and leans on its handle, creating a bassy moan. He says he's tempted to press harder to make the windows rattle, but there are too many customers around. Elsewhere in the Mission Pawn/House of Stuart are a 1927 slot machine, two Elvis figurines and a carousel horse. At one end of the room is a long display case filled with coins -- some recent, others more than 1,000 years old (a Roman coin issued between 613 and 630, which is selling for a paltry $395). Though it's the rarest coin in the place, there just isn't any demand for it, Decaro says -- even though it's pure gold and weighs three-quarters of an ounce. The Roman coin is a steal, he says; an ounce of gold goes for $420, with or without 1,300 years of history behind it. The wall near the coin case is hung with framed currency from the original 13 colonies and the Confederacy. There's also the typical pawnshop fare, including a wall of guitars, guns, keyboards, a drum set, other electronics and, of course, jewel ry -- diamonds ranging from $20 to $20,000, pearls and a $500 Rolex.