I always like to teach the basics on a flight sim, so that at least they can get an idea of what happens to the needles at a more reasonable cost to the student. However no sim can truly replicate what happens for real.
I'll try the CAA and see what they say. I don't think it will need a formal recommissioning, since the only reason it is off-line is that a fuse went in the power supply and the previous owners wouldn't pay to get it repaired. A matter of just a few pounds really.