When my S code was 'found' in the UK a few years ago, in order to export it, it needed to be proof fired & stamped.
Whilst the norm would be various stamping as below:
It thankfully found a considerate section 5 dealer who arranged for the single BNP Birmingham proof stamp placed under the grip.
In these unavoidable circumstances, the alternative being deactivated, I think it came off rather well with its brush with the authorities.
