They look very nice, but seldom are any good. if a mouse gets in there, the radiator is scrap. It is impossible to clean them except by soaking in a hot tank, and mouse nest is tough to get out.
Although they're not correct for Model As, many Classic cars came from the factory with them. They probably worked really well when they were new but once they're clogged they're a nightmare. My 1928 Packard had one that I fought for several years before I sold the car. Brassworks might offer new cores but I'm not sure.