i don't think you can ever really talk about coercivity for superconducting Pb.
Yes, you can probably make plots of something that suggest that you could define something similar, but remember that Pb is type II meaning the situation is quite tricky: the curve would look different depending on whether or not teh Pb was superconducting when the field was applied, the strength of the field compared to Bv1 etc.
In short. It is all quite messy.
I've never used Opera. Does the program explicitly allow you to defined superconducting screens?