Not easy to replace ,I suggest repairing and living with it!
We had a crack in Our Old Rig right where the moulded Soap Dish was located. I found some plastic Bowl or Wash Tub in a similar Color at a Thrift Store that I carved up to make a patch. Used Epoxy for Plastic to fuse the Part over the Crack then filled the edges with a mixture of epoxy and plastic filings! Yep drill holes at the ends of the crack!
It just takes a bit of ingenuity to make these sort of repairs, and not being so hard on oneself if the end result isn't incredibly amazing!