Sea-Doo › Sea-Doo 1503 4-Tec Top End Rebuild Kit (1mm Over) Image 1 of 1 Sea-Doo 1503 4-Tec Top End Rebuild Kit (1mm Over) $745.71 Full rebuild kit for engines needing 1mm overbore restoration. Add To Cart Added! Full rebuild kit for engines needing 1mm overbore restoration. You Might Also Like Sea-Doo 580 Top End Rebuild Kit (1mm Over Platinum, 77mm) $258.46 Sea-Doo 580 Top End Rebuild Kit (.75mm Over Platinum, 76.75mm) $258.46 Sea-Doo 580 Top End Rebuild Kit (.5mm Over, 76.50mm 1992-1996) $180.20 Sea-Doo 1503 4-Tec Top End Rebuild Kit (.5mm Over) $546.83 Sea-Doo 1503/1630 4-Tec Top End Rebuild Kit (100.96mm) $546.83