I bought a blower just like this today. Same handle same 3 legged stand and no numbers whatsoever. Mine also seems to be in good condition.

I think THAT 'green' is the original color! There's significant debate out there about what the original factory color of the Champion blowers was -- no one seems to really know, definitively and all the old catalogs are black and white. My Champ 400 has a very faded-out blueish-green around some of the lettering and in the crevices -- 90% surface rust, but a teeny bit of what looks like this teal-green color in your pics. Can anyone confirm? Is that the ORIGINAL Champion / Lancaster factory color??? I'm asking because I'm going to resto mine back as close to original as possible and really wanted to get the original color identified.