The screws in question are zinc-plated hardened steel screws (1 1/4 in) for use with heavy duty fire-rated stainless steel interior door hinges of unspecified grade.
There is a theoretical risk of galvanic corrosion, given that both the zinc plating and carbon steel are anodic to stainless steel. However, I've come across a number of resources that claim that the risk of this is negligible in a typical mild-moderate-humidity urban interior environment.
I've seen a number of SS hinges that have BZP screws in them with no visible corrosion.
Given their relative availability, is it worth the extra effort to track down stainless steel screws for stainless steel hinges, or should I just stick to using galvanized steel screws?