Speaking for myself and my company, these numbers 'm' and 'c' (I assume you mean the Paris law 'm' and 'c'--da/dN=C*(Delta-K)^m), are almost as valuable to us as our own families--these material constants are proprietary and considered company secrets; the reason is it costs us a lot of money to do the experiments needed to determine these two constants, and we certainly aren't going to just give them away because someone needs them. However, you might consider looking in a local university library that has some material (ASM or ASTM) handbooks, you might get some nominal values there.
From NASGRO database, 17-4 PH H1025, Paris law constants are C=3.4e-10, n=3.42 for da/dN in units "inches/cycle" and Delta-K in units of ksi-sqrt(inches)
