Any vintage bike for sale is unlikely to be 100% original, whatever that means, lots of frames have been repainted and had a colour change, groupsets and wheels have been swapped. My view is really who cares, cycling is a personal thing, and it’s what works for you, I’ve owned very original vintage bikes and they don’t always ride that well, the gearing is limited and they’re heavy, a subtly updated bike is often much better to ride.
I sold an updated, custom built
Ribble 653 recently, completely non-original, with a carbon fork and modern brifters, I had a lovely email from the new owner saying how great it was to ride.
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