Are these moldings stainless steel, and can you braze them?

Bill, I think your going to have to seek out a trim repair specialist. Someone who does this daily. Or source used and restore.
Or, an excellent tig weldor, who has modern low amp, or pulse equipment, whos experience is mostly aluminum sheetmetal.
Or an excellent gas weldor of sheetmetal/trim using modern alloys, fluxes etc.
Personally I might attempt stainless with my antique Tig machine but what you have is most likely aluminum, and I bet they used poor quality, just good enough.
I think flame would be your best bet.
good luck