I tried the spray lube and everything else that's recommended for stuck shifters. Nothing worked at all. I took it into my bike shop and they checked, then agreed with my assessment. There are no new DA 7800 series shifters available anywhere and DA isn't repairable like Ultegra or 105. Rather than buying a used one that's going to fail, I want to go to something new, even if it's a pair of NOS Ultegra 10-speed or 105 10-speed.Have you tried spraying WD40 or some aerosol degreaser inside the shifter? They rarely 'die' they just get sticky. Try that before pronouncing it dead. You can find shifters online yourself if you take a couple minutes to look.