By artificial gravity, I assume you mean using rotation to produce centrifugal force?
Correct. While we usually think of "artificial gravity" as some sort of sci-fi graviton thingy, von Braun used to term to describe the effect of rotating wheel in space.
That means that to get a full G of apparent gravity, you need a station with a radius of nearly 225 meters. Obviously, you could probably make do with less than a full G.
The original proposal by von Braun and Willy Ley was a 3-deck, rotating wheel with a diameter of 76 meters. Rotation would have been 3 RPM to provide artificial gravity of 1/3 earth normal. Since the effects of weightlessness were not known at the time, I believe von Braun intended the gravity to make the station more operationally efficient rather than meet the health needs of the crew.
I just don't see that being likely until we have a more efficient way than rockets to get material into space
You have to remember that they had the power of the Saturn V at their disposal. No weight was too heavy! No craft too large! And with the Nova drawings on the board, it was only a matter of time before mankind was the master of his solar system!
Of course, the fact that NASA was spending a fairly sizable chunk of the GDP on space exploration was lost on these engineers. There was not going to be a Nova, the Saturn V was seen as too expensive, and their ideas for a space station were simply too grand.