I've used outdoor string lights and then just put the lowest wattage LED's in there.
Those motions sensors aren't going to run long enough. If you wanted to put them out say April 1st and if we were in similar regions(NorCal) and if your goal was to simulate the daylight + twilight hours difference between April 1st and June 21st, the difference roughly being from 6am-8pm, versus 5am-9pm, then you'd want to run them an extra two hours. Those little batteries in there probably can't run for that long.
If you don't have access to an outlet and need to build a little solar setup, then we'd have to do some math and start with which bulbs you're going to use. If you were going to use ten 10w bulbs for 2hrs, then you're only looking at 200wh, which you could easily put together an overkill kit just from a trip to Harbor Freight.