I suspect hand loading primers in "the day" may have been done, however, methods, tools and materials would have been much different. What may have been "run of the mill" supplies then could no longer be duplicated in the same manner and then there is the toxicity problems that didn't seem so important back then. Antique machinery parts that have to be custom made typically cost more than it's worth. Primers are likely the same. It would be fascinating to know more about how they did do these things.