There was a thread by Scurv
recently regarding some dodgy 3d walls. One of the posts on the page I linked to talks about printing them up from a service, although the poster doesn't say which one. There were savings to be made, but whether they bring to cost down to a reasonable amount is another matter.
Those look like fairly beefy models, so I would think they'd be quite expensive, no matter what route you take. I'm sure others with 3d printing experience will have things to say

You could always use the 3d files to print a master, make a mould and cast the rest of them in resin, which would probably be cheaper. The possibilities that 3d printing opens up are what interest me the most, even if I'm just watching from the sidelines at the moment.