Paul is correct, HIN numbers have specific formats. In 1982 there were two options. In both options, the first three letters, assigned by the US Coast Guard, identified the builder. VYN was assigned to Ria Yachts DBA Victoria Yachts. The next five numbers were the serial number which was at the discretion of the builder. It may or may not include the hull number although most do. In your case it’s pretty likely the 18 was for the model. It is unlikely the 104 is the hull number. That seems too low. 1045 seem too high and doesn’t fit with the format required in 1982.
The last four digits after the serial number were for the date of certification. Keep in mind, model years start in August of the previous year so, for a model year 82, the format could be either 4 numbers (ex. 0981 for September; or 0482 for April). Or the second option would be M82 (model year 1982) followed by a letter from A-L representing the month built (A=August 1981, B=September 1981… F=January 1982 etc.).
The HIN you are seeing doesn’t completely match either of these formats. Are you 100% on the number? Either way, it doesn’t appear the HIN helps ID the hull number.
Sorry this doesn’t help answer your question.