Electrical Demon?

How old is the gas and filter ??

Did you take the gas tank out and clean it,,

Next time it stalls, look down the carb and see if it squirts gas when you move the throttle.. if it doesn't squirt,
Take the fuel filter off and see if you can blow thru it..

Your symptoms also match a progressively plugging fuel filter, or perhaps water in the fuel..

hope it helps