The State Racing and Gaming Commission Thursday approved a financing agreement that lets the owners of the Sioux City Belle purchase an Illinois casino. Argosy Gaming Chief Financial Officer Dale Black sought commission approval as he says the Iowa riverboat is key to the Illinois deal.He says the Sioux City Belle will be part of the collateral for financing the purchase of the Illinois casino. Black says the 475-million dollar deal won’t hurt the company’s financial standing.Commission members asked Black when the company would put some money into improving the Sioux City boat. He says they’re waiting until Sioux City officials decide where they want the boat to permanently dock.Black says the city is looking at two potential sites for the Belle to make as a permanent home.