You'll have to take the boat to the marine police for inspection with a cert. note stating where & who you got it from. then DMV will issue the paper work. just did it for a used boat ( 11') I bought years ago w/o paper work.
WHAT!!!!! I bought a 12 foot row boat last year, went to the dmv with a hand written bill of sale and serial number. I filled out a couple forms and in 15 minutes had a registration, hull number, and sticker. All for under 20 bucks. I didnt have to take it anywhere.