Well, you haven't had much luck with your question so far.... Can't help much with Leopards.... I know there're some in the area around Tomales, Bodega and Humoldt Bays but I've never targeted them. There's a couple of guys that know something about targeting Leopards over there but they're generally tight lipped about it.
If you haven't already checked them out, you might call Eureka Fly Shop. They're up on all bay/estuary/surf fishing up there. As for Kayak stuff, try:
This place is in Humboldt Bay and rents kayaks or, if you already have one provides a place to buy kayak gear up there. They should, also, have info about any fisheries inside or outside the bay. Lots a good Halibut fishing up there.
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