My understanding AIC ratings is that to be rated a breaker has to be installed in an enclosure listed for that breaker. So if you put a Square Breaker in a GE enclosure you will not have a listed assembly with a known withstand rating.The title probably explains it - but is it a violation to put say a 400AMP Square D Breaker into a 400AMP rated GE enclosure?
All other things being equal it seems to me that would be enough of a violation for an inspector to fail an installation.
That said I know that both Square D and Eaton custom make breaker & bus assemblies for old big switch gear and MCC bucket for obsolete equipment. I also know that Eaton makes kits to replace the interiors of FPE panels and I am pretty sure all of that is listed somehow or another.