From what I read on google (quick search), the boat was mass produced in Poland from early 70s to early 80s and desribed as a capable coastal cruiser. Apparently, not sinkable due to floatation compartments filled with foam. In many cases owners have removed the foam to gain additional storage space. You might have a hard time finding VIN, as it simply may not have one. Boat was manufactured in two versions - centreboard only and with shoal keel/centreboard (better version) - seems this is the version you have.