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thank you for getting back with the additional information.
in reviewing the thread posted by KenNC was reminded that we had another example posted which came through with the second generation 3TTT Record handlebar stem & 3TTT Gran Prix handlebar. my error
. the nominal accepted launch date for the second generation Record model stem is 1974 but it may have been available at the OEM level in Italy sometime in 1973. previously had the idea that it was very slightly late for the bike.
being able to see the other examples gives you an opportunity to see how they were kitted.
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pedal note -
don't feel too bad about the dustcap for the Shfeffield model Corsa Nr. 655 pedal. they are not a very practical model for most riders. the lateral distance between the inner and outer "spurs" is quite narrow such that unless a rider has rather small/narrow feet they will probably be unable to fit their shoe into them. this has caused me to refer to them as the "ballerina pedal."
once you have enough forum posts you can post an ISO/wanted notice for the dustcap. it may be that a member has a hopelessly damaged Sheffield snoozing in a parts bin which yet has its dust cap.
another possibility, if you wish, is to check the web site subito.it. this is a kind of craigslist for Italy which regularly has bicycle parts offered. the prices there are typically below those of ebay.
here are two images of the 655 in case it may be of help -
they were offered in both a chrome and a zinc finish.
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