Identify these rocker arms

Sorry.. No... If you look at the Crane picture just above there is a defined fairly sharp spline reinforcing the rocker with a diagonal stiffener on the far side at the pivot/oil hole...

The original picture has wider spline without the diagonal reinforcement... My guess is they are 273 rockers that have had the friction adjusters removed & locking adjusters added...

I just went and looked at 273 rockers.. Nope...

FWIW they aren't Isky either, Isky has that diagonal reinforcement too... Along with hardened wear pads

Maybe Erson...