Either you aren't seeing the serious paddlers or you don't recognize a dry suit. I personally agree with dry at those temps, but I paddle with one person who can tolerate a brief swim in a thick wetsuit down into the 40's. (With a good cag on board.)
I strongly suspect that you are not remotely ready for Lake Superior. Get to the folks recommended in this thread for a proper intro to paddling that lake.
Hardshell Kayak Sail Rigs
Touring Kayak Paddles
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