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Congratulations on this nice find!
Thanks for sharing with the forum.
Frame constructed with Agrati lugset of "BRIANZA" pattern.
Chainset, saddle and rear mech a good deal later than machine. Original chainset likely three-arm cottered steel by either Magistroni or Way-Assauto. If we take shift levers to be original then rear mech would have been either Campag Gran Sport or Campag Sportman. If we take Huret Allvit 600 front mech to be original then rear mech would have been Huret Allvit and shift levers Huret. Since the bottom bracket cable guide is also Huret think a Huret gear ensemble would be the more likely original.
Cycle a one up from the bottom sort of model.
Its Campagnolo Sportman hubs enjoyed a fairly brief production life in the early-to-mid 1960's. Their axle locknuts will be marked with a specific year.
Stem & bar appear to be Ambrosio Champion.
Pedals appear to be Sheffield but cannot see them quite well enough for a specific model ID.
Saddle pillar size will be an indication of tubing. About the best one might expect is Falck plain gauge. This would exhibit a size of 26.4mm.
If you have any specific questions will try to help.
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