Just managed to get access to a computer again and was in the throws of trying to catch up on emails I have to send when I spotted this CR item in my post.
It's very impressive looking bike built around an excellent frame. I'm not too sure whether the seller knows what he is selling. In the first place he calls the machine French..then in the text of the advert he refers to the builder being in Genova, which, I assume is Genoa on the north coast of Italy along from the French Riviera.
I know of two cycle shops in France with the name Bertetto. The first one was in Bellegarde in the Ain region ie east of Lyon and towards the Alps and Annecy; the second one is in Nice on the Riviera..
I knew the first Bertetto quite well..his shop was in a back-street sheltered away underneath the immense motorway viaduct that runs right over the valley in which Bellegarde is situated...and he was a frame-builder who built some very impressive machines. I think that he will have retired by now as I used to visit him in the 1980s and early 90s..
The other Bertetto is still trading but I do not know if he builds frames..
Logic would suggest that the Bellegarde Bertetto built this frame..he was an excellent builder and he bronze-welded quite a lot of his frames..and his workshop was less than an hour's drive from Pierrebenitte in the southern suburbs of Lyon where Mr Rezze used to sell his Excell tubing..although, of course, the tubes came from a factory in the eastern suburbs of Paris..and it is still there...but never was owned by Mr Rezze.
My euros are definitely backing the Bellegarde Bertetto
Norris Lockley..Sancerre France.
PS I hope to be in Lyon next week looking for a few Reyhands at the local brocantes sales.