My husband and I recently acquired a 1973 27' Ericson from his uncle and we're trying to register and insure it. His uncle had it dry-docked for years and never registered it. He never had a title, only a bill of sale from the previous owner that has since been misplaced. I found 5 digits that were imprinted 27-185 however my insurance company is requiring a 12 digit HIN. I'm assuming the beginning of this would be ERY. The last 4 digits would contain 73. I guess if I knew the month it was certified and which method is used (example M73_ or _ _73) I could figure this out. Any thoughts or suggestions?