Bought this just because I needed some parts that were on it and as I was the only bidder....never the less. it looks a descent frameset, so before part with it, I'd like to know what it actually is. Japanese? American? British/ Italian perhaps?

FRAME - Champion No.1 sticker, could be false as had respray (red colour originally). Serial number on bottom bracket 4592. Rear dropouts Tange TR. Seatpost 27.2mm BSA threads. Weight (size 57) with headset cups is 1900 grams
FORKS - Champion sticker. Tange TF-R dropouts. Tange Made in Japan 2H on steerer. Weight 720 grams.