If you plan on doing a lot of paddling, purchasing a VHF would be a wise course of action. Contact Industry Canada about obtaining a radio license. Search patterns differ depending on how old the data is. If the Sea King is equipped it may have Direction Finding Capability and be able to identify where the radio signal comes from. Fire off a flare appropriate to the light conditions i.e. smoke during the day.
Movement attracts attention.
Try splashing and waving your arms about. Keep in mind that only your head and shoulders can be seen. White blends into white caps and dark hair is hard to see. Sea dye markers colour the water orange and can be easily seen. Don't bother with sound.