Where can I find more keys to progress through the Water Temple?

I am on my second or third playthrough of the game, but it's been a long while since I played the entire game through in a long time. I have just gotten to the water temple and used my keys in the wrong order, instead of opening two consecutive doors, I opened only the doors to the room with keese at the entrance and platforms with hookshot targets, and the room that leads to the high level water rise switch. I havn't beaten Dark Link to get the longshot, so I still have the hookshot. I have both the map, the compass and the Biggoron Sword. Is there a way to work around my problem, or do I need to restart the game? I have gotten the key you get when you defeat the four spiked balls, and the key you get by opening the gate with two clams behind it and going into the room beyond. It would be very helpful I someone could provide information on the locations and how to get each of the keys in the dungeon.