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I am having trouble finding the seal for the toliet so it will stop leaking.
You don't list the make of the toilet, here's a source for American Standard bottom of page.
You normally use a felt gasket but in many instances I have used a regular bowl wax but forming it to the back of the toilet then resetting the toilet to the wall and caulk it. Your best chance of finding a felt gasket is at a plumbing supply house