Pedro_orange,
Prugnat 62S Lugs were used by Holdsworthy on a lot of their Claud Butlers from takeover in 1959 until the mid 70's. Oiler on top of BB would confirm pre or if on bottom post 1965. Fork crown looks pre 1965. Likely 60's sometime. Could be a Challenge, Classique, Velo Capital, Velo Valentino or European. No way of knowing but if Universal 61 brakes are original likely a Classique. Does it have a Lamp boss? More pics would be good too.
Date from serial off bottom of BB or fork stem would help in searching the model.
I've been working with a couple of other fellows on Retrobike collecting Claud Butler serials in period above and so far have serials of more than 60 frames. Developed a date prediction table. If you go to my Flickr account with pics of frames you should be able to get a likely date from prediction table and from that look at relevant year(s) of Kilgariff's catalogues to better sort model possibilities.
https://www.flickr.com/photos/76762476@N05/albums
Hope helps. If you are able, I would be interested in knowing number so as to add to our data.
Doug