saw them on Amazon definitely an option seems like lots of guys had issues with fitment and the needle bearings coming apart\burning up but again not sure if that was track situation or just street use
Honestly if it was me with that cam I would try to find an old set of mechanical rockers that we ran years ago. Not so much the 273 rockers as they have those screwy tapered adjusters but an old set of Cranes or possibly another company that offered them. I still see them out there once in awhile. That is unless you are young, have a few extra bucks, and plan on running small blocks for years. Then pony up for Harlan sharps with a 10% off coupon or find a used set and they will last you a lifetime.