Mine is rusted out. The car sat for 6-7 years. Help!

If you can find a replacment, great its the best way to go, or depending on how bad it is you might be able to have it welded up but i doubt it, (make sure its done by a professional or you could blow it up) or option 3, like me you can find an aftermarket fuel cell i got a 16gal with 0-90ohm sender for just over $200.(Gm style fuel gauge required)