The only spares I can find are the shock cords. All Rhode state is to order them from your local distributor.
The hot shoes is part of the main body moulding so getting a replacement may be difficult. However if you still have the 1/4" screw thread in one piece then a hot shoe adapter with a 1/4" screw thread may be a possibility. Be careful though the one I have is all metal so when it's used on a hot shoe you need to insulate the bottom to prevent any problems with the cameras hot shoe