That looks more like a hull identification number, same as the vehilcle identification number on your car.
If it is, it would equate to a Silverton built in March, 1979 according to the code.
I do not know how they assign documentation numbers but I do believe that is from the feds.
Your registration numbers should be 'NJ' followed by four numbers followed by two letters.
That is the numbers that you see on the bow of most boats.
Oh yeah, if it is the HIN, there is one too many digits.