Yes, OEM U-Joints will fit. Those U-Joints you have now are undersized Spicers with a sleeve that adapts them to the OEM opening. As an alternative, Powertrain Industries has a listing for a Pantera U-Joint. They are slightly longer than OEM U-Joints, so they supply them with slightly thinner snap rings. If I recall, the OEM application for these U-Joints is a '70's Toyota 2wd pickup driveshaft.
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