Sliding window roller

The picture of 87-007 was perfect but the problem is my roller is only 1/2 the size. Its only 1/4 inch wide,5/16 high, 1 inch long. All the windows in my house need
replacement roller assemblies, and I am having a difficult time finding
this. if you can help me with this I would greatly appreciate it. also the
window this one is for is 8 foot by 4 foot with 2 sliders, very expensive to
replace.