SAE-AMS 6264 is fairly close:
STEEL, CARBURIZING GRADE, BARS, FORGINGS, AND TUBING, 1.2CR - 3.2NI - 0.12MO (0.14 - 0.20C).
"These products have been used typically for carburized parts which require high minimum core hardness with a narrow range, but usage is not limited to such applications."