General Avia F22 Pinguino

I’m sure all enthusiasts of Italian light aircraft will know that Stelio Frati passed away earlier this year. Like most amateur pilots I’ve always admired his aircraft and one that caught my imagination was the F22 Pinguino. It only had a short production life and not many were built and those that come on the market seem to have the same aura as Ferraris i.e. expensive. However I still retain the interest and after some diligent Googling I have found information on most of the production run. However I can’t find any reference to those with construction numbers 9,17,19,20,22 and any after 26. All help gratefully received.

PS Avion Ancien, peutetre vous pouvez m’aider?