As long as the frame is in good shape, i.e. no rust, yes, it's a good candidate and a good price at $100. The propane tank and the porcelain coated cast iron grates are worth that price alone. New warming basket and shelf will cost about $30. Only other things to look at really are the burner tubes and the flavorizer bars. Don't worry if the tubes look rusty, that's just their nature. Just make sure they are solid and not rusted through. Same with the flavorizer bars. If needed, you can pick up replacement burners and flavorizer bars on Ebay for much less than what Weber charges. For the flavorizers, you'd need to decide if you want to go the cheap route and get some bars that will need to be replaced in 3-5 years, or grab a set from RCPlanebuyer that should last 10 years or more.
As Sramsey noted, the grill looks like it just needs to be cleaned up a little at this point. If you want, you could mask off the grill box and paint it without removing it from the frame.