these look pretty good at these prices http://www.apmex.com/Product/62591/MintDirect®_2011_5_oz_Silver_ATB_Chickasaw_OK_10_coin_tube.aspx
I did a quick search and I couldn't find any cheaper. I just buy junk silver at spot prices to amass silver. I hardly ever pay a premium on silver and that is what a I base my prices on. I guess $4 an oz isn't really that big of a mark up if you like the coins. Especially when the mint is asking $205 each (which seems a little crazy to me).
