you would need to model it.

This is not so hard.
What's rough stone?
Boulders, flat stacks, what?
I assume irregular rectangles.

Working in plan view as an elevation [ie; laid down], you'd build a matrix of irregular rectangle meshes with undulating surfaces. Do an infill with mortar and bob is your uncle.

The panel is "stood up" by making it a library obejct from a 3D view from wherever you think the top of it should be. This will make it into a panel applied to wall faces.

You might like to emulate a StoneCAD image to make your stone match their stone.... for a good texturemap overlay.

I am not sure, how much help this could be, but here is how I model the attached stone wall image.

I made 2 profiles, one with the entire stone and the other with the mortar finish and them place them on to the model, this i did for one of our client who is about to print their 3d model from my file.

I will attach remaining pics in the next posts.

Here is the Stone Profile

Here is the Cement Mortar Profile, I generally give this slightly more thickness than the stone profile.

Nice stuff guys, I copied this thread into the Tips and Tricks section.
Keep them coming!