Need A New Fuel Tank For My 87' V20 O/B

[sgnhis]

Greeting! Well it's time for a new fuel tank :/ Can I purchase one with the exact same specs as the old one anywhere online? My boat mechanic has a buddy who can build me one but they move very slow down where I keep my boat and they charge us "come here's" extra it seems. If any one can shed some light on this it would be much appreciated! And a early HAPPY NEW YEAR to all!!