Yamaha Petrol Fuel tank RD 200 / 200DX, possibly RD 250 or RD400 from late 1970’s to early 80’s.
OK, I will get some dimensions made and you can decide if it’s right for your needs.
It’s a very tidy RD tank that appears to have been repainted. It has a few nicks here and there but it comes with the petrol cap and key.