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frame -
fork crown is Vagner model Nr. 11+
dropouts are Simplex (Juy) Nr. 881 & 881B
fork ends not well shown, would expect them to be Simplex Nr. 932 & 933
shell is a BOCAMA pattern. here it is on a Flandria Champion Mondial of 1979 -
eyelets on taper tubes resemble NERVEX Nr. 887
seat stay top - as stated earlier by Hudson308 not a structural problem. if you envision a respray then you can have it repaired. if you wish to retain present finish then spray some anti-rust product and leave as t'is.
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pedals look to be 1950's era Atom 700, or whatever was its predecessor of that epoch.
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wonder if headset may be a TWF pattern
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