Sounds extortionate but that seems to be the going rate for a new pump from Toyota. I wouldn't write off your current pump straight away. Little bits of metal can jam the impellers and cause issues. If you're mechanically minded, it's a fairly simple process to strip it down, clean it and refit with new fluid. If that doesn't work, I'd be looking for a secondhand part from a low mileage car. These can be had for around £100.