I think the Western Hobbycraft trolley is probably your best bet. I think there are still a few available for sale. The larger Superstreets curve should work okay if you want to do 3-rail--I know the Peter Witt will run on that curve.
I wish there were more Trolleys readily available in O scale. It can be very frustrating, which is why I mainly do my trolley modeling in HO.
Jeff C