can you post a pic of the wheel sidewall? Now that you have 10 posts.
I'm using a double pivot caliper rim brake on a rear wheel with a disc hub and non-machined sidewalls. Works fine. But, if your rims' sidewalls do not have flat surfaces suitable for braking, you may be out of luck on rim braking with your new wheels.
Disk brake adapters might do the job for you but that's not a sure thing.