It doesn't look like the frame has been repainted from what I can see in the photos. It looks like there is a heron on the fork crown, so the fork is a replacement. It originally had center pull brakes, since there is a cable stop on the seat tubes, and a black spacer in the headset where a center pull cable stop would have been.

You need a better method of measuring your seat tube diameter. If it were mine, I would take to my LBS and have them measure it - the cost should be minimal or gratis (if you are a customer).