I think Greenline sell Eleocharis acicularis, but I am not positive.
Some of your hairgrass isn`t looking too good at the moment. This may be due to the fact that it is the emerged growth that is dying off to make way for the emersed growth, or it needs a little more separating. I suspect it could be both, but what you definitely need to do is cut off all the grass down to substrate level to allow the emersed growth to come through quicker. Eleocharis sp can be a real algae magnet if you don`t get things right at the start.
Dave.