A roller rocker system would be difficult, but not impossible to fabricate. It would be necessary to find a Torrington-style bearing that could be installed into the rocker arm, and a reduced-diameter rocker shaft would have to be fabricated, ground to a very smooth finish, and then casehardened. The rocker tip probably couldn't be modified for a roller. The cost would be considerable, and I imagine the small demand for such a system would make it virtually a one-off custom fabrication situation. Bring money!
Jerry

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