The producers of NBC's "The Restaurant" might be betting on "The Casino" for their next reality hit. Sources said Mark Burnett and Ben Silverman are working on a spinoff of "The Restaurant," which chronicled the behind-the-scenes action surrounding the opening and the running of a Manhattan restaurant headed by chef Rocco DiSpirito. "The Casino" would take a similar insider look at the workings of a casino. Burnett has been spotted scouting possible locations and meeting with casino owners in Las Vegas, though sources stressed that the project is still in early stages of development. "The Restaurant," from Mark Burnett Prods., Silverman's Universal-based Reveille and Magna Global Entertainment, built up nicely in the ratings week-to-week, regularly ranking as the top Sunday program in the adults 18-49 demographic in the second half of its run.