First time I’ve ever heard that, do you have any documentation on Chrysler doing a recall on master cylinders?
They used the disc brake MC with ports on the engine side on B bodies from ‘68-70. 3 model years. Back 20 years ago when I was buying and selling a lot of NOS master cylinders, I saw those (casting 2226821)with date codes into the early to mid 70s, so if they recalled that style, it’s interesting that Bendix was still selling them as replacement parts into the mid 70s.
There were several aftermarket versions available over the years too. Someone sold one with bosses on both sides of the casting and machined ports into the side required, probably was EIS or Wagner. I worked for Brake Parts Inc and we didn’t have that style with our United line and later Raybestos.
And someone sold one for a couple years in around 2005.
Back to the OPs question, Ram man does have a sketchy reputation. If you have an original master cylinder and you need to have it restored, the go-to reliable source to rebuild master cylinders is Brake and Equipment Warehouse in Minneapolis. They may do boosters too, not sure.
If you don’t have cores to restore, then unfortunately you need to search all the online sources and swap meets.
NOS or rebuilt OEM parts used to be fairly easy to find 20 years ago. They’re still out there but much harder to find now and expensive!