Adding Bronze Bushings to Ductile Iron Rockers

I recently had a failure on a bronze bushed aftermarket Crane iron BB rocker on the dyno. Half of the bushing came out and tied up the rocker which in turn caused the lash cap to spit out. Luckily we caught it right away and was able to replace the rocker and finish dynoing. I have been looking for a couple replacements since with no luck as Crane is out of business. Last Saturday I stopped by a friends shop who races SuperStock and low and behold he had a set of factory stock non bushed rockers that I bought from him on the spot. My car is just a street car and will not see anything over 6500 rpms.