Alternative Standards of GOST 1577-95 Type 5

I work in a company where is made structures and boilermaking, and there's a trouble, the customer company has sent us a material specification call 2012 and they suggest and alternative international standard: "GOST 1577-95 type 5" which is a russian standard. But it's not commercial in my country, I want to know if someone knows about another alternative for this material.

Chemical Composition:

%C: 0.52 - 0.60 %Cr: 0.4
%Si: 0.4 %Mo: 0.1
%Mn: 0.6 - 0.9 %Ni: 0.4
%P: 0.045 %V: -
%S: 0.045 %Nb: -
%N: - %Ti: -
%Al: - %Cu: -
%Cr+Mo+Ni: 0.63

Mechanical Properties at Room Temp. (Machined. Not heat threated)

(DIM) (TENSILE STRENGHT) (HARDNESS)
(mm) (MPa) (HB)

(0 -16) (-) (-)
(16 - 40) (610 - 910) (181 - 269)
(40 - 63) (610 - 910) (181 - 269)
(63 - 80) (610 - 910) (181 - 269)

I hope you can help me, I'm a mechanical engineering student and I wanted to know everything that I can.

Greetings from Peru!