I would guess there are, especially with all those tasty quarry/stone biomes lying around :3
Anyway....
I can't decide if it should be stronger than Brickwall or weaker than brickwall. I suppose stronger, wouldn't make sense to add a tier in-between. Especially because everyone would have brickwall by the time it is added anyway. Though stone can be arguably easier to acquire than clay/bricks, it could require larger stones - like "stone slabs" (you cut a boulder into a slab (like you do for Querns or Runestones) and then you place the slab inside the Building Plot.) That would complicate things a bit.
Also, I think it would be cool - if possible - for Stone walls to allow players on top of them. I think that some shenanigans could achieve that if they're limited to straight segments (as all walls are) and to the grid lock... Wouldn't mind the limitation if it allowed us to walk on walls

Anyway, not really a concrete idea... Just some loose, random thoughts. Stone walls + archery = win.
PS:
Stone walls + new "Drop" option on Boiling Cauldrons filled with Tar on top of walls = DOUBLE WIN.