Looking for replacement sliders

These rollers were broken--broken rim of plastic around outside and what looks like broken clips on the ends. No identifying marks on the windows. The opening for the roller assembly is 1.375" X 0.450". Rollers are 0.530" in diameter. The windows are large and heavy. I would actually like to find a replacement that would fit the opening but have a larger flange that could be screwed or otherwise mounted to the windows in order to be more robust supporting the heavy windows. I believe there is enough play in the window to have a slightly raised rolling mechanism.