The machines are indeed from Academy and Elenco, with some minor modifications. Between the two of them, most of Leonardo's inventions are covered. Between the two manufacturers, I think I prefer Elenco's - they make the larger of two armored cars. However, it seems that Elenco are much harder to find, I'm not sure if they are no longer making the kits. The big steam cannon is an old model from AMT that I found on e-bay.