Double mattress (PO6 Cosham)

Hi there Freeglers, can anyone help me out of a notty problem? I bought a new bed from a local dealer, but the mattress is awful, springs sticking in you where it seems not to have been finished off properly. So I need to find a decent mattress so my wife can get a good night's sleep and not wake up feeling like a plank. Any help, much appreciated. Thanks Norman