I was recently told they were doing a refurb on the hide at Rye Meads.
Some years ago the perch the kingfisher was using too far away from the hide and the only person who got good photos was a chap with a Canon 400mm prime with a x2 converter.
There is a good place on the river Stour near Christchurch but as far as I am aware, it's not been on the regular perch for a while as we believe it is feeding 2 different nests.
I've also been told they've been seen at a couple of places here in Basingstoke but I've never see them myself.
I spent a year on various sites trying to shoot Kingfishers so I know how you feel.
There are othe sites in Hampshire such as Barton Mill and Anton lakes in Andover, Basingtoke Canal in Ashvale in Surrey and Lakeside reserve which is also in Surrey.
I've seen a kingfisher on the Basingtoke Canal and also at Lakside a few times.
There are various privately owned hides you can pay to rent as well.
I've also been told by people more in the know than me that it's not worth trying to shoot them during breeding season and it's better to wait until autumn / winter.