Wood screen door trolley
A quick learner from New jersey says:
March 16, 2016
I have a 9 foot long Pella door with 2 stationary panels on either side and a 3-foot door in the Middle with built-in blinds. It is approximately 17 years old the tubular trolley that the screen door screws to snapped. That aluminum tube is 25 inches long and the screw holes are 26 inches on Center the diameter of the wheels r 11/16 of an inch
Paul from SWISCO responded:
March 18, 2016
Please see our 80-054 Pella screen door trolley. This may be what you are looking for.