I have not seen that on any original cars. I've only seen cylindrical types - before, during, and after 1967.
I can say that in 1980 when my Dec 66 SJ Mustang developed a leak in the typical cylindrical 2B091-B version, I went to the Ford dealer to by one, and one that externally looks the same as the one you pictured. In the box was a new shorty brake line.
I just rebuild my original (glad I saved it) with a kit I bought from you last week. I still have the 1980 version out in the garage and will add pictures later on.
By the way having a heck of a time getting the piston out of the distribution block (the one that drives the low level sensor). The grease gun will be next.