Dear Dominique,
I think your idea to present at the GPR conference is a good idea. You are right that many users of
GPR people little about seismic processing so some set examples,flows and data would be useful.
I incorporated the GPR data and flows you and Guy presented at the summer workshop into a tutorial for the Seismic Unix GUI which I have been developing for students (on the github).
Please let me know if I can help, although I do not have access to too many GPR data sets.
Best,
Juan Lorenzo