You could try these guys, maybe they can rebuild your current one?

The bigger tanks were less common in the older Dodge vans. Really hard to find new tanks and sending units for them.

- Rich

1991 Dodge B250 Zephyr Conversion. "Bi-frost" 74,000-ish original miles and counting.
- 318TBI; has headwork and other bolt on upgrades. Runs strong and smooth!
- Powertrax locker
- 3" aluminum radiator.
- Rear air springs, rebuilt suspension, steering stabilizer.