Power steering kaput

Hi, I've posted about this before, the PS on our K12 fails periodically but turning the engine off and back on again seems to clear the fault. It was only happening occasionally before, now it's happening more regularly. Took it into our local garage, (they're good and they fix any car), who checked it out and said the error code was saying it was the motor that was at fault. New parts would cost £1340, which didn't include the cost of Nissan supplying new codes. So for now, we're limping along, restarting the engine when the problem kicks in. We seem to be over a barrel on this - having the problem fixed with new parts worth more than the car, I've been told you can't get recon parts for this for the K12, secondhand parts not reliable and how do you get around the code issue? There must be someone out there who can fix this at a reasonable price? Any help appreciated, I'm London based. And useless with spanners.