I don't mean to "call out" Bill here, he has been a great asset to the Mopar hobby over the years, and I have dealt with him both as a customer and sold/traded him parts, and hope to again in the future. It is just that when I read his ebay listings and his online descriptions of many of the master cylinders there seems to be an implication that these are restoration correct parts. By talking about how "Bendix was the original supplier" and stating that these are "genuine Bendix" parts in these listings, I feel that some people could be fooled into thinking they are buying parts that are correct for a restoration. They may bolt on correctly and function fine, and if the price is competitive, great, but I just don't want to see anybody showing their restored car at a car show and thinking they have a OEM correct part on their car when it is just a commonly available aftermarket part. I can spot an aftermarket master cylinder from 10' away, but many can't, and by pointing this out I hope I prevent some people from being disappointed. Whether or not the box said Bendix is irrelevant as the box doesn't get installed during the restoration, the part does, and the box gets tossed!
The Bendix company based in South Bend Indiana that made OEM brake parts was sold to the German company Robert Bosch in the 90's, you won't find any "Bendix" parts on any new cars today, you will find "Bosch" parts. Bendix aftermarket is based in Rhode Island IIRC and still exists, but they just source parts from other companies and distribute them under the "Bendix" brand name.
I used to work for a major aftermarket brake parts manufacturer, who supplied Bendix aftermarket for many years, along with many other customers, so that is why I am familiar with all the behind the scenes on brake parts.