Crudely made, indeed! The lip, for all its flaws, appears to be fairly late, 1870 or so, I think. I'm not certain that the bottle has a pontil scar -- I don't see any raw edges on the glass. Is the indentation actually the evidence of a "centering knob" in the bottom of the mold?
I am not sure, there is no mold seams on the bottle and the top of the glass is uncentered from the rest of the bottle. Their is I line of glass on one side that looks like a seam but only goes halfway down.