sorry to hear you havent sold him yet. Did you think about taking him back to your lfs for some credit . Might be the only way of getting a return on your investment.
14" rhom? as in the PIRANHA? In Massachusetts where they are illegal? That's why a pet store won't take it.
You could try Seaworld in Salem,NH they take trades for credit and they will also order whatever kind of fish you are looking for.