New Jersey 18? $50 Dollar Note

It appears genuine to me. This is what is called a remainder note. It was printed for issuance by the Bank in question, but was never actually issued hence why there is no serial number, date, or signatures. A Sussex Bank $50 example in high AU or low uncirculated condition is worth about $30. An uncirculated example grading at 64 or 65 would go for about $50 or $60. Anything grading higher seems quite rare and would be worth more. I haven't seen any sold that were actually issued, its possible that the bank went bankrupt before actually issuing any of the notes or decided to cancel the issuance of the series.