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one does not encounter seat stay plugs this nice on a base model frame/cycle

if this were a base model one would expect it to exhibit a "bullet" type seat stay treatment, for example

this makes me suspect it to be a one up from the base sort of model

it may be constructed with some manner of quality plain gauge tubeset such as ZETA from A.L. Colombo, or Z50, or some manner of Falck

an easy check is seat post diameter opening; if frame were constructed with one of these tube sets would expect this dimension to be either 26.2mm or 26.4mm

edit: oops, see you have given it as 26.2mm

quite possible that all braze-ons other than chain stay stop are post-manufacture additions, the brake cable guides you mention appear they may be a GIPIEMME product

date estimate: 1975

seat stay plugs are a helpful item here

would think they would have to be investment cast (lost wax)

the first commercially available investment cast frame bits came out in 1973 and were from the Italian firm of ROTO (Rampinelli)

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