Trainman2001,
FWIW, picked these up yesterday at my LHS and they fit perfectly on my Atlas track, looks like they would fit well on Ross track also. They're kind of pricey, but they are very nice. They are heavy die cast, have a spring bumper and have set screws to hold them in place. Just thought you might be interested, if so, they are Lionel 6-62283, here is a link...