You will not find either gold or silver under market value. In fact you will pay more then the market value. The reason is simple. There are 2 prices on gold and silver. There is the paper price and the physical price. To obtain physical metal you will always pay a premium over the spot price on the COMEX. I just bought 100 ounces yesterday. I buy the Silver Canada Maple Leaf Coins and I paid $14.95 per coin. The total with commissions, shipping and wire transfer fees was $1566.16. So that works out to $15.66 an ounce.
There are many places you can go to buy silver bars and coins. The price differs from broker to broker and product to product. I use the following company.
http://monex.com/index.html
There are others too but I havent used these yet for silver but Ive used these 2 for gold .
http://www.amergold.com/
http://allamericangold.com/index.html