I have no experience with either part but am looking at a new Master Cylinder and will buy one of these which is a Bendix part for the Get 1 MC - direct replacement "supposedly". I have not done my research yet on direct part number interchangeability. Both suppliers have an excellent reputation. I would not waste money on a rebuild given it is 53 years old.
https://www.okp.de/xtc2/Ferrar...122.html?language=en
https://www.superformance.co.uk/308/brakes.html
As for the booster, per Steve, I would have it rebuilt.
ABS Power Brake, Inc. in Orange, CA. ABS Power Brake (CA)