Did or does Bachmann make a large Calliope car that would run with a Bachmann Circus set?
CK,
Bachmann did not make a calliope car, but did make a calliope wagon that rode on a flat car.
It was Item number 98373.
Here is a list of all Bachmann Circus Cars except for the new Ringling Bros Cars: Scroll down to see the list.
http://www.bachmanntrains.com/home-usa/board/index.php/topic,19456.0.html