There are quite a few selections at Costco. You might want to search for Glucosamine Supplements.
http://www.costco.com/Common/Category.aspx?whse=BC&Ne=4000000&eCat=BC|589|770&N=4013450&Nr=P_CatalogName:BC&cat=31149&Ns=P_Price|1||P_SignDesc1&lang=en-US&topnav=
http://www.costco.com/Common/Category.aspx?whse=BC&Ne=4000000&eCat=BC|589|770&N=4013450&Nr=P_CatalogName:BC&cat=31149&Ns=P_Price|1||P_SignDesc1&lang=en-US&topnav=