Bisi sells rockers.

BTW with higher seat pressure you'll need better oil or you'll trash the rockers. Amsoil HDD, Torco, or oil with a Torco Zinc additive.

With the reduction of ZDDP in modern oils for better emissions as well as the fact that most new cars are roller rockers, our older flat tappet engines suffer. On a stock valvetrain boundary lubrication isn't an issue, but with upped spring pressures acting on the rocker, the oil can't do its job being squeezed that hard. And then metal to metal contact occurs and absolutely destroys the rocker arm. This will reduce effective lift and will eventually wear stuff out beyond repair and is bad.

Just an FYI.