Both Fenix and Zebralight (google them) make LED flashlights and headlights with strobe modes. The Fenix also flashes SOS.

I have both. They are great flashlights and in a pinch, they may work even better for you than a heavy, expensive, dedicated strobe that will likely never be needed.

Strobes are standard fare for at sea rescues and military ops, but I would be interested in how often they have been the key to a civilian land rescue.