I assume the chrome pipe, is for an electric shower? You could easily drill a hole through the upper flat ledge of the bath, then run the pipe through a 15mm chrome, compression fitting, tightened against the underside.
Do you still have the broken off, edge of the bath? If you do, you could apply some strong tape to hold it temporarily in place, or maybe some superglue applied along the edge, just long enough, for you to apply car body filler (Plastic Padding), to the unseen back of it, to reinforce it.
If the part is missing, then all can do, is built it up with fibreglass, car body filler, sand it to shape, then paint it white.