Hondabond HT is "...high temperature silicone liquid gasket. Non-acidic, will not corrode aluminum For use in areas not requiring solid gaskets." It comes in a 1.9 ounce tube with a list price of $16.28. Honda part number 08718-0004. Google any part number to find a Honda Dealer selling it online, or use this link to find a Honda Dealer in your area:
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The Honda shop manual says you may also use Loctite 5900; "Flange Sealant, Heavy Body RTV Silicone is a one part RTV silicone that has superior flexibility and adhesion. Provides instant seal. Excellent fluid resistance. Non-corrosive, low odor, low volatility." A 300ml (10 ounce) tube is $46.05. Loctite part number ORS091220166ORS.