Something to look forward to if Prop 19 passes : Swap the Dungeness crab cakes and peasant skirts for lobster rolls and L.L. Bean khakis, and this snug seaside hamlet a few hours north of San Francisco could be a dead ringer for a New England village. (It was a stand-in for Cabot Cove, Maine, in the long-running TV series Murder She Wrote.) But if California voters approve a controversial ballot proposition in November to tax and legalize marijuana for recreational use — and it’s ahead in several polls — some local growers say Mendocino, pop. 900, might become better known as the tourist capital of a “Napa Valley of cannabis.” The notion of opening marijuana-tasting rooms, meet-the-grower tours and ganja-friendly “bud and breakfasts” in Northern California’s pot-farming “Emerald Triangle” is like “tearing down the Berlin Wall. It’s not going to happen overnight,” says Matthew Cohen of MendoGrown. His 12-member association promotes a “sustainably grown medical cannabis industry” in the county, where legal and illicit pot — sanctioned for medical use by California residents since 1996 — fuels an estimated half to two-thirds of an economy once anchored by fishing and timber. Still, he says, passage of Proposition 19 would mobilize entrepreneurs and help jump-start a sluggish tourism industry by putting “Mendocino County on the map as a vision of what cannabis country could look like. The vibration is already here, and if you love (marijuana) enough to smoke it in a coffeehouse, why wouldn’t you want to come out and enjoy it at the source?” They’re going to have to put rubber bumpers along the freeway up there.