This is not a Bank Note. The "Bank Notes" were a series of stamp issues. This is a stamped envelope entire.
Very neat date stamp and cancellation, but the California collectors will have to weigh in on rarity/scarcity. If it was from my collecting area, I'd jump on it.

The masking tape and tear is a negative, but the strike is strong. It is not a duplex device as the two strikes are not oriented correctly.