The Jazz uses a 20" (drivers side) and a 15" (passenger side) wiper blade, Halfords will have them, try and buy the BOSCH ones though, as they are better quality.
The rear wiper (as with most cars) is a dealer only part, but you can slide out the worn or torn rubber insert and wiggle a new one into the existing blade holder if you are careful, most car parts places sell lengths of rubber wiper blade insert.