The J-truck rocker replacements are a direct fit.
You can use Wagoneer rockers too, but only if you just need the outer skin like I did. The difference is the sill plate on the Wagoneer rockers. They have a cutout for the B-pillar so there isn't a continuous run of sheetmetal on top. Cherokee (2-door) rockers are next to impossible to find and they fetch a hefty price when you do. I bought the Wagoneer rockers because they were available on e-bay and even cheaper than the J-truck ones. And I only needed the outer skin, so the sill was of no significance to me.
The J-truck rockers are readily available.
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